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1

Peptide Hormones of anterior Pituitary (testies of the brain)

Porlactin (sparta), hGH (growth, lipid & carb. metabolism), beta-endorphin (nno pain!), Adrenocorticotropic hormone (secretion of the gluco- mineralo- & sex-coticoids),

2

Glycoprotein Hormones of anterior Pituitary (testies of the brain)

TSH (stim. Thyroid hormoes), FSH (Growth of sex, Red Week d3 & primary spermatocytosis, acts with LH), Lutenizing H (Leydig cells - Testosterone, Red week),

3

prolactin. (peptide)

300 Functions (sparticus!) Pituitary. Peptide hormone. Stim. Milk production & Reg. Immune function. Cell Cycle growth- differentation - antiapoptotic

4

Testosterone. Source?

Testes.

5

epinephrine. Function?

sympathetic stress response

6

Prolactin. Source?

Anterior Pituitary

7

Glucocorticoids. Source?

Adrenal Cortex. Steroid. Metabloism of Glucose

8

Oxytocin. Action?

milk letdown, uteral contractions

9

somatostatin

delta cells of pancreas, stomach, intestine. Inhibit hGH, inhibit TSH - suppress gastrointestional hormones

10

hGrowth Hormone. Source?

Anterior Pituitary

11

aldosterone

mineralocorticoid, secreted in the adrenal cortex, acts on distal convoluted tubule of kidney to promote sodium-potassium exchange

12

glucagon

peptide hormone. Pancreas, alpha cells. More blood glucose!

13

progesterone (steroid). Action?

Menstration, pregnancy, embryogenesis. Mineralcort. Recept. Antagonist - Sperm homing signal (ca++, CatSper)

14

T3, T4

Tyrosine-based. Follicular cells of thyroid - Iodine required (goitre). Increase basal metabolic rate! Protein sysn. & long bone growth

15

Thyroid Hormones (T4, T3). Source?

Thyroid

16

Atrial Natriuretic Factor

Powerful vasodilator (peptide); secreted byatrial myocytes; targets kidney and increases urination to decrease blood pressure. Reduce H20, Na+, K+, Adipose on circulatory system

17

glycogen

multibranched polysaccharide polymer that serves a storage form of glucose

18

estrogen (steroid)

Secreted in the follicle, prevents maturation of more than one follicle at a time

19

calcitonin (peptide)

Parafollicular cells of the thyroid, reduces blood calcium concentration, inhibits the normal process of bone resorption, inhibits renal tubular cell reabsorption of Ca2+

20

what increases blood [glucose]?

glucagon, epinepherin, cortisol

21

ADH

Retain and Constrict! Water absorption by kidney - collecting duct & distal convoluted tubule; increased blood pressure (always digging holes aquaporin-CD channels)

22

Oxytocin. (peptide)

Stimulates uterine contractions during labor, milk secretion during lactation.

23

Mineralocorticoids. (steroid)

Salt and Water balanceIncreases water absorption in kidneys

24

parathyroid hormone (peptide)

produced in parathyroid glands in responce to low blood calcium, increases bone resorption and consequent calcium release, increases intestinal calcium uptake, and promotes calcium reuptake at the kidney

25

Corticotropin-releasing hormone (CRH) (peptide)

released by hypothalamus. Stress response. Stimulates the pituitary to secrete ACTH - metabolism & parturition (pregancy)

26

what regulates [Ca++]?

parathyroid hormone (PTH) and calcitonin

27

hGH

Growth of nearly all cells (human growth hormone)

28

Thyroid Hormones (T4, T3). Action?

Stimulates metabolic activity.

29

How do peptide hormones act?

via secondary messengers.

30

luteinizing hormone (LH)

secreted by the anterior pituitary, stimulates the growth follicle, surge causes ovulation

31

epinephrine (amino acid derivative)

adrenal medulla. Sympathetic stress response (rapid). Heart rate, blood vessel & air passage diameter, metabolic shift

32

Estrogens

Growth of mother sex organs; causes LH surge

33

Melatonin. Action?

Unclear in humans... thought to have possible roles in circadian rhythms, as antioxidant, in immune system.

34

PP: oxytocin (peptide)

targets the breast to influence milk letdown. Also targets the uterus to influence contractions

35

FLAT PEG? 

Fsh, Lh, Acth, Tsh, Pro, End, Gh.

36

Source?

Anterior Pituitary

37

3 effects of aldosterone

1. to increase urinary excretion of potassium 2.to increase interstitial sodium concentration 3. to increase water conservation

38

AP: luteinizing hormone (LH) (peptide and gonadotropic)

effects ovary and ovulation.effects testes and testosterone synthesis

39

How do steroid hormones act?

via a hormone/receptor binding to DNA.

40

EP- glucagon (alpha cells secrete) (peptide)

increase blood glucose and decrease glycogen and fat storage

41

melatonin

pineal, unclear to humans

42

thyroid hormone

thyroid, stimulates metabolic activity

43

lutenizing hormone

anterior pituitary, stimulates testosterone release in males and ovulation in females

44

mineralcorticoids

adrenal cortex, increase water reabsorption in kidneys

45

Testosterone

TESTES: male characteristics; spermatogenesis

46

insulin

pancreaslowers blood glucose and storage of glycogen

47

erythropoiletin

kidneystimulates bone marrow to increase production of erythrocytes

48

atrial natriuretic hormone

heartinvolved in osmoregulation

49

Thymosin

THYMUS: is involved in T-cell development during childhood.

50

Milk production and letdown

Oxytocin and Prolactin

51

Regulation of Ca

Parathyroid hormone and Calcitonin

52

Regulation of blood glucose

Insulin and Glucagon

53

follicle stimulating hormone

anterior pituitarystimulates follicle stimulation in femalesspermatogenisis in males

54

thyroid stimulating hormone

anterior pituitarystimulates the release of thyroid hormones from thyroid

55

Regulation of [Ca2+]

Parathyroid hormone and Calcitonin

56

Growth hormone

anterior pituitary; Promotes bone and muscle growth; inhibits uptake of glucose by some cells; Stimulates breakdown of fatty acids; Stimulated by GHRH and inhibited by somatostatin

57

Adrenocorticotropic hormone

ANTERIOR PITUITARY -> ADRENAL GLAND: increases growth and secretory activity of adrenal cortex

58

Erythropoeitin

KIDNEY -> BONE MARROW: increases RBC synthesis

59

epinephrine and norepinephrine

adrenal medullaincrease blood glucose level and heart rate

60

Luteinizing hormone

ANTERIOR PITUITARY -> OVARY/ TESTES: ovulation or testosterone synthesis

61

atrial natriuretic peptide

heart; involved in osmoregulation and vasodilation

62

Atrial natriuretic factor

HEART -> KIDNEY: increases urination to decrease blood pressure

63

Hormones that increase blood [glucose]

Glucagon (polypeptide derivative), Epinepherine (amino acid derivative), Cortisol (steroid / glucocorticoid)

64

Adrenocorticotropic hormone (ACTH)

ANTERIOR PITUITARY -> ADRENAL GLAND: increases growth and secretory activity of adrenal cortex

65

Thyroid hormones (T3, T4)

thyroid; Necessary for growth and neurological development in children; Increase rate of cellular respiration and rate of protein and fatty acid synthesis/degradation; High levels inhibit TRH and TSH

66

Atrial natriuretic factor (ANF)

HEART -> KIDNEY: increases urination to decrease blood pressure

67

Releasing and Inhibiting Factors (peptides)

Gland: HypothalamusTarget: Anterior pituitaryEffect: Modify activity

68

Growth Hormone (GH) (peptide)

Gland: Anterior pituitaryTarget: N/AEffect: INCREASE bone & muscle growth & cell turnover rate

69

Prolactin (peptide)

Gland: Anterior pituitaryTarget: Mammary glandsEffect: Milk production

70

Thyroid Stimulating Hormone (TSH) (peptide)

Gland: Anterior pituitaryTarget: ThyroidEffect: Tropic; INCREASE synthesis & release of TH

71

Adrenocorticotropic Hormone (ACTH) (peptide)

Gland: Anterior pituitaryTarget: Adrenal glandEffect: INCREASE growth & secretory activity of adrenal cortex

72

Luteinizing Hormone (LH) (peptide)

Gland: Anterior pituitaryTarget: Ovary / TestesEffect: Ovulation / Testosterone synthesis; gonadotropic

73

Follicle Stimulating Hormone (FSH) (peptide)

Gland: Anterior pituitaryTarget: Ovary / TestesEffect: Follicle development / Spermatogenesis

74

Antidiuretic Hormone (ADH/vasopressin) (peptide)

Gland: Hypothalamus / Posterior pituitaryTarget: KidneyEffect: Water retention

75

Oxytocin (peptide)

Gland: Posterior pituitaryTarget: Uterus / BreastEffect: Contraction / Milk ejection

76

Thyroid Hormone (TH, thyroxine) (amino acid deriv.)

Gland: ThyroidTarget: N/AEffect: Child: physical & mental developmentAdult: INCREASE metabolic rate & temp

77

Calcitonin (peptide)

Gland: Thyroid / Thyroid cellsTarget: Bone / KidneyEffect: LOWERS [Ca2+] via 1) into bone, 2) decrease reabsorb. by gut, 3) excrete in urineInhibits osteoclast activity

78

Parathyroid Hormone (PTH) (peptide)

Gland: ParathyroidsTarget: Bone / Kidney / Small intestineEffect: Raises [Ca2+] via OPPOSITE of calcitonin

79

Thymosin (children only) (peptide)

Gland: ThymusTarget: N/AEffect: T cell development during childhood

80

Epinephrine (modified amino acid)

Gland: Adrenal medullaTarget: N/AEffect: Sympathetic stress response (rapid)

81

Cortisol ("glucocorticoid") (steroid)

Gland: Adrenal cortexTarget: N/AEffect: Long-term stress response; INCREASE blood glucose & protein catabolism; DECREASE inflammation & immunity; etc.

82

Aldosterone ("mineralcorticoid") (steroid)

Gland: Adrenal cortexTarget: KidneyEffect: INCREASE [Na+] reabsorption to inc. blood pressure

83

Sex Steroids

Gland: Adrenal cortexTarget: N/AEffect: Only impor. when adrenal tumor overproduces these, causing masculinization or feminization

84

Insulin (via β cells) (peptide)

Gland: Endocrine pancrease (islets of Langerhans)Target: N/AEffect: DECREASE blood glucose; INCREASE glycogen & fat storage

85

Glucagon (via α cells) (peptide)

Gland: Endocrine pancreas (islets of Langerhans)Target: N/AEffect: INCREASE blood glucose; DECREASE glycogen & fat storage

86

Somatostatin (via SS-δ cells) (peptide)

Gland: Endocrine pancreas (islets of Langerhans)Target: N/AEffect: INHIBITS many digestive processes

87

Testosterone (steroid)

Glands: TestesTarget: N/AEffect: Male characteristics, spermatogenesis

88

Estrogen (steroid)

Gland: Ovaries / PlacentaTarget: N/AEffect: Female characteristics, endometrial growth, ossify the epiphyseal plate

89

Progesterone (steroid)

Gland: Ovaries / PlacentaTarget: N/AEffect: Endometrial maturation, pregnancy

90

Atrial Natriuretic Factor (ANF) (peptide)

Gland: HeartTarget: KidneyEffect: INCREASE urination to dec. blood pressure

91

Erythropoietin (peptide)

Gland: KidneyTarget: Bone marrowEffect: INCREASE RBC synthesis when blood O2 falls

92

PTH (hormone)

Bone: Stimulate osteoclast activityKidneys: INCREASE reabsorb. of [Ca2+]; stim. vitamin D -> calcitrolGut: Indirectly INCREASE [Ca2+] absorbtion

93

Calcitriol

Kidneys: INCREASE reabsorb. of phosphorusGut: INCREASE rabsorb of [Ca2+]

94

Diastereoisomers

Nonidentical sugars within same family (both are ketoses/aldoses and have same number of carbons)

95

Conversion of Fischer projection to Hawthorne projection

Any group on right points down; any group on left points up

96

Reducing sugar

Any monosaccharide with hemiacetal ring (-OH on C-1)

97

Alpha anomer

Has the OH group of the C-1 trans to CH2OH substituent (pointing down)

98

D configurations

Positive rotations; hydroxyl group of the highest number chiral center on the right

99

Henderson-Hasselbalch Equation

pH = pKa + log ((conjugate base) / (conjugate acid))

100

pH = pI

Titration curve is vertical; added equal amounts of amino acid and base

101

Prosthetic groups

Major roles in determining protein function; lipids in lipoproteins; carbs in glycoproteins; nucleic acids in nucleoproteins

102

Aldose

Aldehyde sugar; gluceraldehyde is simplest

103

Beta anomer

Has the OH group of the C-1 cis to CH2OH substituent (pointing up)

104

Mutarotation

Spontaenous opening and reformation of hemiacetal rings when exposed to water; alpha or beta anomer can be formed

105

pH = pKa

Solution is in a buffer zone; titration curve is horizontal; deprotonated and protonated species in equal concentrations; buffering capacity max

106

Amino acid properties

All optically active due to chiral alpha carbon (except glycine); all L-enantiomers; drawn with amino group on left; all have S configurations (except cysteine); exist as internal salts in neutral pH

107

Aldonic acids

Oxidized aldoses; when hemiacetal ring is in open chain aldehyde form it is oxidized to carboxylic acid

108

Amphoteric

Species that act as both a base and an acid depending on the environment

109

Furanose rings

Five membered rings formed from five carbon aldoses or six carbon ketoses

110

Glycoside

Acetal formed as a result of alcohol combining with hemiacetal monosaccharide in acidic conditions

111

Tollen's reagent

Reduction of Ag+ to form metallic silver; detects presence of reducing sugar

112

Sugar enantiomers

Same sugars in different optical familes (D-glucose and L-glucose)

113

Pyranose Rings

Six membered rings; formed from six carbon aldoses or seven carbon ketoses

114

Anomers

Cyclic stereoisomers that differ about the new chiral carbon

115

Glycosidic linkage

C-O bond between alcohol and hemiacetal monosaccharide formed under acidic conditions; most common glycosidic linkage between two monosaccharides between 1' and 4' positions

116

Epimers

Diastereomers that differ at only one chiral center

117

Anomeric carbon

Carbon that becomes chiral in a sugar ring; carbon attached both to the oxygen in the ring and a hydroxide group

118

Polysaccharides

Cellulose, starch and glycogen; composition of D-glucose monosaccharides linked by 1,4'-beta-glycosidic bonds

119

Benedict's reagent

Indicates presence of reducing sugar; red precipitate of Cu2O

120

Alpha carbon in Amino acid

Between amine and carbonyl group; chiral except in glycine;

121

Ketose

Ketone sugar; dihydroxyacetone is simplest

122

Denaturation

Melting; destroys tertiary structure of protein

123

Conjugated proteins

Function from covalently attached molecules called prosthetic groups

124

Enthalpy (H)

The sum of the internal energy of the system plus the product of the pressure of the gas in the system and it's volume: ΔH=ΔΕ-PΔV H=total energy of the system; E= bond energy of products or reactants in a system; P=pressure; V=volume

125

ATP

Adenosine Triphosphate - considered the most important potential energy storage molecule in cells. Stores energy in the ester bonds between it's phosphate groups.

126

Gibbs Free Energy ΔG=ΔH-TΔS

This is a practical way to discuss thermodynamics. A change in available energy is equal to the change in enthalpy (total energy of the system) plus the product of absolute temperature (Kelvin) and change in Entropy.

127

Celsius to Kelvin conversion:

K=C+273

128

Entropy (S)

A measure of disorder or randomness.

129

Exergonic Reaction

Energy outward, proceeds with a net release of free (available energy). Because chemical mixture loses free energy, G decreases and G is negative for exergonic reactions. These are spontaneous reactions.

130

Endergonic Reaction

Is a reaction that absorbs free energy from it's surroundings. This reaction essentially stores free energy in molecules (G Increases) ΔG=positive. Endergonic reactions are nonspontaneous.

131

A cell does 3 main kinds of work:

Chemical work - pushing of endergonic reactions that would not occur spontaneously. Transport Work - pumping of substances across membranes against direction of spon. movement. Mechanical Work - beating of cilia, contractions of muscle cells, movement of chromosomes during cellular reproduction.

132

Spontaneous Processes

ΔGs own without outside help it must increase the entropy of the universe.

133

Is the trend of the universe more towards entropy or order?

Entropy. Think of room of people moving around giving off heat (this adding to the entropy of the universe).

134

The rate determining step in a reaction sequence is:

The step with the highest activation energy.

135

For a system to put out heat:

There must be a temperature difference that results in the heat flowing from a warmer location to a cooler one.

136

ΔG (change in "free"/available energy)

G=the portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell.

137

First law of thermodynamics

States that energy of the universe is constant, energy can only be transferred and transformed, but never created or destroyed. Implies that when energy of a system decreases, the energy of the rest of the universe must increase.

138

Second law of thermodynamics

States that the entropy of the universe tends to increase. For a process to occur spontaneously it must increase the entropy of the universe.

139

2 types of energy

Heat energy - movement of molecules. Potential Energy - energy stored in chemical bonds.

140

Exothermic Reactions

Reactions with a negative ΔH, these reactions liberate heat. Most metabolic reactions are exothermic (this is how homeothermic organisms such as mammals maintain a constant body temperature.)

141

Endothermic Reactions:

Reactions with a positive ΔH require an input of heat and are called endothermic.

142

Equilibrium

The point where the rate of reaction in one direction equals the rate of reaction in the other.

143

Anaphase

sister chromatids separate

144

apoenzymes

enzymes without their cofactors

145

Golgi Apparatus

#NAME?

146

Perioxysomes

are ubiquitous organelles in eukaryotes that participate in the metabolism of fatty acids and other metabolites. They have enzymes that rid the cell of toxic peroxides.

147

Genes

Coding regions of genetic material

148

Coarse Adjustment Knob

Focuses the image

149

Chloroplasts

Contain chlorophyll and are responsible for the generation of energy using water, carbon dioxide and sunlight

150

autoradiography

2nd technique (among microscopy, ¢rifugation to examine cells) uses radioactive molecules to trace. use to study protein synthesis: labeling amino acids with radioactive isotopes. used to study mech of DNA & RNA synthesis

151

hydrogenosomes

is a membrane-bound organelle of ciliates, trichomonads and fungi which produces molecular hydrogen and ATP. This organelle is thought to have most likely evolved from mitochondria.

152

cisterna

comprises a flattened membrane disk which makes up the Golgi apparatus.

153

Budding

equal replication followed by unequal cytokinesis

154

Endocytosis

process whereby the cellular membrane invaginates and engulfs material into the cell

155

Endothermic reaction

one that requires energy input

156

Histones

Organizing proteins that wind linear DNA

157

Spindle fibers

made from microtubules; radiates outward from centrioles

158

oxygen

final electron acceptor in the electron transport chain, resulting in the formation of a water molecule

159

Metaphase

chromosomes align at the equatorial plate, which is equidistant to the two poles of the spindle fibers

160

Centrifugation

3rd method for examining cells (microscopy&autoradiography) Spinning down test tubes at high speeds to fractionate cells based on density

161

Prokaryotes

-Simplest of all organisms -Include all bacteria -Cell wall does not enclose any membrane-bound organelles-Genetic material is contained in a single circular molecule of DNA reproduction

162

Cajal body

are spherical sub-organelles found in the nucleus of proliferative cells like tumor cells, or metabolically active cells like neurons. In such cells they are bound to the nucleolus by coilin proteins.

163

axoneme

is the inner cytoskeletal structure of eukaryotic cilia or flagella.

164

microfilament

are the thinnest filaments of the cytoskeleton found in the cytoplasm of all eukaryotic cells. These linear polymers of actin subunits are flexible and relatively strong.

165

plastid

are major organelles found in plants and algae responsible for photosynthesis, storage of products like starch and for the synthesis of many classes of molecules such as fatty acids and terpenes.

166

38 ATP

Prokaryotic ATP production per glucose molecule

167

Chymotrypsin

Cleaves peptide bonds around the amino acids phenylalanine, tryptophan, and tyrosine in a variety of polypeptides

168

Enzyme-substrate complex

Complex between the enzyme and substrate

169

Noncompetitive inhibition

inhibitor binding to an allosteric site instead of the active site, which induces a change in enzyme conformation

170

Diaphragm

Controls the amount of light passing through the specimen which is important for image control

171

Nucleolus

Subsection of the nucleus where the ribosomal RNA is synthesized

172

nuclear lamina

is a dense fibrillar network composed of intermediate filaments made of lamin that lines the inner surface of the nuclear envelope in animal cells.

173

actin

is the protein which serves as the monomeric subunit of microfilaments, one of the three major components of the cytoskeleton, and of thin filaments which are part of the contractile apparatus in muscle cells.

174

Carbohydrates

sugar polymers that can be broken down during digestion and then stored in the liver for later use in a polysaccharide form

175

Cell division

Process whereby a cell replicates its DNA, doubles its organelles and cytoplasm and then splits into 2 daughter cells

176

phase contrast microscope

permits the study of living cells

177

Cytoskeleton

Made of 3 types of proteins: actin filaments, intermediate filaments and microtubules

178

Induced fit theory (stress ball)

enzyme fits the substrate

179

tubulin

is one of several members of a small family of globular proteins. The most common members this family are the proteins which makes up microtubules.

180

undulipodium

is a general term for a 9+2 organelle containing a microtubule array such as eukaryotic flagella and cilia.

181

Interphase

Consists of the G1, S, G2 and M phases

182

G2 phase (postsynthetic gap)

final stage before cell division; quality control; make sure that there are enough organelles and cytoplasm to make two new daughter cells

183

Active Transport

net movement of a solute against its concentration gradient; requires energy

184

2 types of cofactors

-small metal ions -small organic groups

185

Endoplasmic reticulum (shipping department)

-Responsible for proper production and sorting of materials from the cell -Two types: smooth and rough

186

Cell Theory

1. All living things are composed of cells2. The cell is the basic functional unit of life3. Cells arise only from preexisting cells4. Cells carry genetic info in the form of DNA

187

Facilitated Diffusion (Passive transport)

simple diffusion for molecules that need help

188

CoQ10

a vitamin that is found in the inner mitochondrial membrane of the cell and helps make ATP

189

Effects of pH

Enzymes function properly when this is optimal

190

topogenic sequence

is a segment of a protein that ensures it acquires the proper orientation during its insertion into the endoplasmic reticulum.

191

Binary Fission

seen in bacteria, this is a type of asexual production in which a single DNA molecule attaches itself to the cell membrane and duplicates itself to while the cell itself grows in size; the cell then invaginates or pinches inward to create two identical daughter cells; results in two cells of equal size

192

Nucleus (city hall and public library)

**commonly tested on MCAT-Control center of the cell

193

Allosteric sites

the active site is present as well as at least one other site that can regulate the availability of the active site

194

nuclear export signal

is a short amino acid sequence of 5-6 hydrophobic residues in a protein that targets it for transport from the cell nucleus to the cytoplasm through the nuclear pore complex.

195

3 key phases in cellular respiration

1. pyruvate decarboxylation 2. citric acid cycle 3. electron transport chain

196

Telencephalon

The cerebral hemispheres.

197

Replication

The duplication of DNA

198

M-line

The center of the sarcomere

199

Lipoprotein

Large conglomerations of proteins, fats, and cholesterol that transport lipids in the bloodstream. (chylomicrons are a type of lipoprotein).

200

MHC

Major Histocompatability complex, a set of proteins found on the plasma membranes of cells that help display antigen to T cells. MHC I is found on all cells and displays bits of proteins from within the cell; this allows T cells to monitor cell contents and if abnormal peptides are displayed on the surface, the cell is destroyed by killer T cells. MHC II is found only on macrophages and B cells. This class of MHC allows these cells (known as antigen presenting cells) to display bitts of "eaten" (phagocytosed or internalized) proteins on their surface, allowing the activation of helper Ts --> thus further activating immune response.

201

ENZYME-SUBSTRATE COMPLEX

enzyme bound to substrate

202

Lamellae

Concentric circles of bony matrix which surround the Haversian canal

203

LH

stimulates ovulation and estrogen in females and testosterone secretion in males

204

Operator

A specific DNA nucleotide sequence where transcriptional regulatory proteins can bind.

205

Phosphofructokinase

The enzyme that catalyzes the phosphorylation of fructose-6-phosphate to form fructose-1-6-bisphosphate in the third step of glycolysis. This is the main regulatory step of glycolysis. PFK is feedback-inhibited by ATP.

206

Submucosa

The layer of connective tissue directly under the mucosa of an open body cavity.

207

Each nucleotide contains one nitrogenous base that is either a ______ or _______

purine, pyrimidine

208

Macrophage

A large, non-sepcific, phagocytic cell of the immune syste. Macrophages frequently leave the bloodstream to crawl around in the tissues and perform 'clean up' duties, such as ingesting dead cells or cellular debris at an injury site, or pathogens.

209

Amphipathic

The characteristics of amolecule that has both polar (hydrophilic) and non-polar hydrophobic) regions, e.g. phospholipids, bile, etc.

210

FADH2

The reduced from (carries electrons) of FAD (flavin adenine dinucleotide). this is the other main electron carrier in cellular respiration (NADH is the most common).

211

Spermatogenesis

Sperm production; occurs in human males on a daily basis from puberty until death. Spermatogenesis results in the production of four mature gametes (sperm) from a single precursor cell (spermatogonium). For maximum sperm viability, spermatogenesis requires cooler temperatures and adequate testosterone.

212

Serum

Plasma with the *clotting factors removed*. Serum is often used in diagnostic tests because it does not clot.

213

Microfilament

The cytoskeleton filaments with the smallest diameter. Microfilaments are composed of the contractile protein actin. They are dynamic filaments, constantly beig made and broken down as needed, and are responsible for events such as pseudopod formation and cytokenesis during mitosis.

214

Kin selection

Organisms behave altruistically if they are closely related to successfully reproducing organisms

215

Atria

Thin walled chambers of the heart (blood is received in these)

216

Endoskeleton

Skeleton which is internal to the organism, supporting framework of animals

217

AUG

List the coding sequence for start codon

218

Natural selection

The mechanism described by Charles Darwin that drives evolution. Through mutation, some organisms possess genes that make them better adapted to their environment. These organisms survive and reproduce more than those that do not possess the beneficial genes, thus these genes are passed on to offspring, making the offspring better adapted. Over time, these genes (and the organisms that possess them) become more abundant, and the less beneficial genes (and the organisms that possess them) become less abundant.

219

Formed elements

The cellular elements of blood; erythrocytes, leukocytes, and platelets.

220

Endotoxin

A normal component of the outer membrane of Gram-negative bacteria. Endotoxins produce extreme immune reactions (septic shock), particularly when many of them enter the circulation at once.

221

Prolactin

A hormone secreted by the anterior pituitary that tarets the mammary glands stimulating them to produce breastmilk.

222

Krebs cycle

The third stage of cellular respiration, in which acetyl-CoA is combined with oxaloacetate to form citric acid. The citric acid is then decarboxylated twice and isomerized to recreate oxaloacetate. In the process, 3 molecules of NADH, 1 molecule of FADH2, and 1 molecule of GTP are formed (per acetyl-CoA)

223

Sister chromatid

Identical copies of a chromosome, produced during DNA replication and held together at the centromere Sister chromatids are separated during anaphase of mitosis.

224

Testcross

A genetic cross between an organism displaying a recessive phenotype (homozygous recessive) and an organism displaying a dominant phenotype (for whic the genotype is unknown), done to determine the unknown genotype.

225

Tetanus

when the frequency of stimulation is very fast and individual contractions fuse and the muscle smoothly and fully contracts

226

Jejunum

The middle (approximtely 40%) of the small intestine.

227

Reflex arc

A relatively direct connection between a sensory neuron and a motor neuron that allows an extremely rapid response to a stimulus, often without conscious brain involvement.

228

Orgasm

A function of the reproductive system controlled by the sympathetic nervous system. In males, organs includes emission and ejaculation; in females it is mainly a series of rhythmic contraction of the pelvic floor muscles and the uterus.

229

Diffusion

The movement of a particle (the solute) in a solution from its region of high concentration to its region of low concentration ( or down it concentration gradient).

230

Centromere

A structure near the middle of eukaryotic chromosomes to which the fibers of the mitotic spindle attach during cell division.

231

Chromosome

A single piece of double-stranded DNA; part of the genome of an organism. Prokaryotes have circular chromosomes and eukaryotes have linear chromosomes.

232

Acetyl-CoA

The first substrate in teh Krebs cycle, produced primarily from the oxidation of pyruvate by the pyruvate dehydrogenase complex, however acetyl-CoA is also produced during fatty acid oxidation and protein catabolism.

233

5' cap

a methylated guanine nucleotide added to the 5' end of eukaryotic mRNA. The cap is necessary to initiate translation of mRNA

234

Binary fission

An asexual method of bacterial reproduction that serves only to increase the size of the population; ther is no introduciton of gnetic diversity. THe bacterium simply grows in size until it has doubled its cellular components, then it replicates its genone and splits into two.

235

Darwin's Natural Selection Theory

Organisms produce offspring; variations may be inheritable and if have survival advantage will be favorable; increase in these traits through natural selection

236

ZYMOGEN; PROENZYME

enzymes in their inactive form; irreversible changed by other enzymes or environmental changes

237

Latent period

Initial period of the simple twitch (time between reaching threshold and onset of contraction); followed by contraction period and relaxation period

238

b-glucose

a anomer of glucose where the hydroxyl group and the methoxy groups are on the same side (cis). Only bacteria break down beta linkages.

239

Mitosis

The phase of the cell cycle during which the replicated genome is divided. Mitosis has four phases (prophase, metaphase, anaphase, telophase) and includes cytokinesis (the physical splitting of the cell into two new cells).

240

Endocrine system

A systme of ductless glands taht secrete chemical messengers (into) the blood - has to be into the blood.

241

Oval window

The membrane that separates the middle ear from the inner ear.

242

Loose connective tissue

Connective tissue that lacks great amount of collagen or elastic fibers (hence, loose), e.g., adipose tissue and areolar (general connective) tissue.

243

Leukocyte

A type of white blood cell; leukocytes are either B or T cells and are involved in disease defense.

244

Secondary immune response

A subsequent immune response to previously encountered antigen that results in antibody production and T cell activation. The secondary immune response is mediated by memory cells (produced during the primary immune respone) and is much faster and stronger than the rpimary response, typicaly taking only a dya or less. THis is not long enough for the infection to become established, and symptoms do not appear, thus the person is said to be "immune" to that particular antigen.

245

Testes

The primary male sex organ. The testes are suspended outside the body cavity in the scrotum and have two functions (1) produce sperm, and (2) secrete testosterone.

246

At what age do first molars appear?

6-7 years

247

Cytosine

One of the four aromatic bases found in DNA and RNA. Cytosine is a pyrimidine; it pairs with guanine.

248

Artery

A blood vessel that carries blood away from the heart chambers. Arteries have muscular walls to regulate blood flow and are typically high-pressure vessles.

249

Bohr effect

The tendency of certain factors to stablize the hemoglobin in the tense conformation, thus reducing its affinity for oxygen and enhancing the relase of oxygen to the tissues. The factors include increased PCO2, increase temperature, increased bisphosphoglycerate (BPG), and decreased pH. Note that the Bohr effect shifts the oxy-hemolobin saturation curve to the right.

250

Crossing over

The exchange of DNA between paired homologus chromosomes (tetrads) during *prophase I* of meiosis.

251

Erythropoietin

A hormone produced and released by the kidney that stimulates the production of red blood cells by the bone marrow.

252

Nucleolus

A region within the nucleus where rRNA is transribed and ribosomes are partially assembled.

253

Mutualism

A form of symbiosis in which both organisms involved benefit from the association.

254

Trophoblast

The outer ring of cells of a blastocyst. The trophoblast takes part in the formation of the placenta.

255

Enteric nervous system

The nervous system of the gastrointestinal tract. It controls secretion and motility within teh Gi tract, and is linked to the central nervous system.

256

LIPID (6)

any biological molecules that has low solubility in water and high solubility in nonpolar organic solvents: Phospholipids, Glycolipids, Fatty Acids, Triacyglycerols, Steroids, Terpenes

257

Citric acid cycle

Series of 8 reactions that extracts energy from Acetyl-CoA by combining with oxaloacetate, regenerating oxaloacetate in the process. Produces 6 NADH, 2 ATP, 2 FADH2 from 2 Pyruvate

258

frameshift mutation

result of deletion or insertion in the DNA that is not a multiple of 3.

259

Frontal Plane

A vertical plane that passes from side to side; it is at right angles to the midsagittal plane and cuts the specimen into anterior and posterior components

260

Gastrulation

the division of the inner cell mass of a blastocyst (developing embryo) into the three primary germ layers. Gastrulation occurs during weeks 2-4 of gestation.

261

Plasma cell

An activated B cell that is secreting antibody.

262

Luteinizing Hormone (LH)

A tropic hormone produced by the anterior pituitary gland that targets the gonads. In females LH triggers ovulation and the development of a corpus luteum during the menstrual cycle; in males, LH stimulates the production and release of testosteron.

263

Rule of multiplication

A statistical rule stating that the probability of two independent events occuring together is the product of their individual probabilities.

264

Transition mutation

A point mutation in which a pyrimidine is susbstituted for a pyrimidine, or a purine is substituted for a purine.

265

Upsteam

Toward the 5' end of an Rna transcript (the 5' end of the DNA coding strand). The promoter and start sites are upstream.

266

Anterioir pituitary gland

Also known as the adenohypophysis, the anterior pituitary is made of gland tissue and makes and secretes six different homrones: FSH, LH, ACTH, prolactin, TSH, and growth hormone. The anterior pituitary is controlled b yreleasing and inhibiting factors from the hypothalamus.

267

Tropic hormone

A hormone tha tcontrols the release of another hormone.

268

Epididymis

A long, coiled duct on the outside of the testis in which sperm mature.

269

Functional synctium

A tissue in which the cytoplasms of the cells are connected by gap junctions, allowing the cells to function as a unit. Cardiac and smooth muscle tissues are examples of functional synctiums.

270

Sertolli cells

Cells that form the walls of the seminiferous tubules and help in spermatogenesis Sertoli cells are also called susenacular cells.

271

POSITIVE COOPERATIVITY

when the first substrate binds to the enzyme and makes a conformational change allowing substrates to bind more easily

272

Macula densa

The cells of the distal tubule at the juxtaglomerular apparatus. They are receptors that monitor filtrate osmolarity as a means of regulatin filtration rate. If a drop is osmolarity is sensed, the macula densa dilates the afferent arteriole (to increase the blood pressure in the glomerulus and thus increase filtration) and stimulates the juxtaglomerular cells to secrete renin (to raise systemic blood pressure).

273

Loop of Henle

The loop of the nephron that dips downward into the renal medulla. The loop of Henle sets up a concentration gradient in the kidney such that from the cortex to the renal pelvis osmolarity increases. The descending limb of the loop of Henle is permeable to water, but not to sodium whereas the ascending limb is permeable to sodium, but not to water (and in fact, actively transports sodium out of the filtrate).

274

Which teeth do children lack?

premolars and one set of molars

275

Organ of Corti

The structure in the cochlea of the inner ear made up of the basilar membrane, the auditory hair cells, and the tectorial membrane. The Organ of Corti is the site where auditory sensation is detected and transduced to action potentials.

276

Nodes of Ranvier

Gaps in the myelin sheath of the axons of peripheral neruons. Action potentials can 'hump' from node to node, thus increasing the speed of conduction (saltatory conduction).

277

How can nucleotides be designated?

The letter code plus the letter code for the number of phosphates

278

Estrogen

SteroidGland: Ovaries/placentaTarget/Effect: female characteristics, endometrial growth

279

anaphase I

separates homologues

280

Progesterone

SteroidGland: Ovaries/placentaT/E: endometrial secretion, pregnancy

281

The start codon is...

AUG

282

Sex Steroids

SteroidGland: Adrenal CortexTarget/Effect: not normally important, but an adrenal tumor can overproduce these, causing masculinization or feminization

283

Cortisol

The principal glucocorticoid secreted from teh adrenal cortex. This steroid hormone is released ruing stress, causing increased blood glucose levels and reducing inflammation. The latter effect has led to a clinical use of cortisol as an anti-inflammatory agent.

284

Villi

(Singular:villus). Folds of the intestinal mucosa that project into the lumen of the intestine; vili serve to increase the surface area of the intestine for absorption.

285

hCG

Human Chorionic Gonadotropin, a hormone secreted by the trophoblast cells of a blasocyst (i.e. developing embryo) that prolongs the life of the corpus luteum, and thus increases the duration and amount of secreted progesterone. This helps to maintain the uterine lining so that menstruation does not occur. The presence of hCG in the blood or urine of a woman is used as a positive indicator of pregnancy.

286

G0

nongrowing state, causes differences in length of cell cycle

287

Glycogenolysis

a term for glycogen breakdown.

288

What is a Fillial Generation?

Progeny

289

Osteoclast

A phagocytic-like bone cell that breaks down bone matrix to release calcium and phosphate into the bloodstream.

290

Operator

A specific DNA nucleotide sequence where transcriptional regulatory proteins can bind.

291

Catalase

The primary enzyme in peroxisomes; catalse catalyzes the hydrolysis of hydrogen peroxide (H2O2) into water and oxygen.

292

Sarcomere

The unit of muscle contraction. Sarcomeres are bounded by Z lins, to which thin filaments attach. Thick filaments are found in the center of the sarcomere, overlapped by thin filaments over one another during contraction reduces the distance between Z lines, shortening the sarcomere.

293

Intron

A nucleotide sequence that intervenes between protein-coding sequences. In DNA, these intervening sequences typically contain **regulatory sequences, however, in RNA they are simply spliced out to form the mature (translated) transcript.

294

Shine-Dalgarno sequence

The prokaryotic ribosome-binding site on mRNA, found 10 nucleotides 5' to the start codon.

295

Regulation of gene expression occurs at the level of...

transcription

296

histones

dna wrap around these globular proteins

297

lipid

biological molecule that has low solubility in water

298

telophase I

nuclear envelope may reform, cytokinesis may happen (if happens => secondary spermatocytes/oocytes, in female one of oocytes is first polar body and degenerates)

299

Glycolysis

anaerobic splitting of a glucose molecule into 2 pyruvic acid molecules, producing 2 net ATP and 2 NADH molecules. First step in cellular respiration.

300

Follicle Stimuating Hormone (FSH)

PeptideGland: Ant. Pit.Target/Effect: ovary/follicle development, testes/spermatogenesis

301

Yeast

Asexual reproduction occurs by budding (small cell pinches from larger one)Unicellular fungus

302

tight junctions

membranes of neighboring cells are attached and the cells are bound together so tightly that no material can pass between the cells or travel past the junction- forming a total barrier to transport and diffusion

303

Exclusion

The removal ( and usually the activation) of a viral genome from its host's genome.

304

Natural selection

The mechanism described by Charles Darwin that drives evolution. Through mutation, some organisms possess genes that make them better adapted to their environment. These organisms survive and reproduce more than those that do not possess the beneficial genes, thus these genes are passed on to offspring, making the offspring better adapted. Over time, these genes (and the organisms that possess them) become more abundant, and the less beneficial genes (and the organisms that possess them) become less abundant.

305

Flagella

A long, whip-like filament that helps in cell motility. Many bacteria are flagellated, and sperm are flagellated.

306

Fibrinogen

A blood protein essential to blood clotting. The conversion of fibrinogen to its active form (fibrin) is among the final steps in clot formation, and is triggered by thrombin.

307

Cilia

A hair-like structure on teh cell surface composed of microtubules ina '9+2' arrangement (nine pairs of microtubles surrounding 2 single microtubules in the center). Teh microtubules are conneted with a contractile protien called dynein. Cilia beat in a repetitive sweeping motion, which helps to move substances along the surface of the cell. They are particularly important in the respiratory system, where they sweep mucus out of the trachea and up to the mouth and nose.

308

Vagal tone

The constant inhibition provided to the heart by the vagus nerve. Vagal tone reduces the intrinsic firing rate of teh SA node from 120 beats/minute to around 80 beats/minute.

309

Cecum

The first part of the large intestine.

310

Tight junction

Also called occluding junctions, tight junctions form a seal between cells that prevents the movement of substances across the cell layer, except by diffusion through the cell membranes themselves. Tight junctions are found between the epithelial cells lining the intestines and between the cells forming the capillaries in the brain (the blood-brain barrier).

311

Tropomyosin

A helical protein that winds around actin helices in skeletal and cardiac muscle cells to form the thin filament of the sarcomere. In the absence of Ca2+, tropomyosin covers the myosin-binding sites on actin and prevents muscle contraction. When calcium is present, a conformation change in tropomyosin occurs so that the myosin-binding sites are exposed and muscle contraction can occur.

312

Induction

The process by which neighboring cells can influence the determination (and subsequent differentiation) of a cell.

313

Receptor-mediated endocytosis

A highly specific cellular uptake mechanism. The molecule to be taken up must bind to cell surface receptor found in a clathrin-coated pit.

314

Retina

The innermost layer of the eyeball. The retina is made up of a layer of photoreceptors, a layer of bipolar cells, and a layer of ganglion cells.

315

Primase

An RNA polymerase that creates a primer (made of RNA) initiate DNa replication. DNA pol binds to the primer and elongates it.

316

Liver

The largest organ in the abdominal cavity. The liver has many roles, including procesing of carbohydrates and fats, synthesis of urea, production of blood proteins, production of bile, recycling heme, and storage of vitamins.

317

Prophase

The first phase of mitosis. During prophase the replicated chromosomes condense, the spindle is formed, and the nuclear envelope breaks apart into vessicles.

318

Homozygous

A genotype in which two identical alleles are possessed for a given gene. The allelles can both be dominant (homozygous dominant) or both be recessive (homozygous recessive)

319

Oxaloacetate

A four-carbon molecule that binds with the two-carbon acetyl unit of acetyl-CoA to form citric acid in the first step of the Krebs cycle.

320

Heterozygous

A genotype in which two different alleles are possessed for a given gene.

321

Amylase

An enzyme that digests starch into disaccharides. Amylase is secreted by salivary glands and by the pancreas.

322

Analogous structures

Physical structures in two different organism that have funcitonal similarity due to their evoluntion in a common environment, but have different underlying structure. Analogous structures arise from convergent evolution.

323

5' cap

a methylated guanine nucleotide added to the 5' end of eukaryotic mRNA. The cap is necessary to initiate translation of mRNA

324

competitive inhibitors

compete with substrate, looks alike, decrease affinity, overcome with more substrate conc

325

nondisjunction

when chromosome does not split during anaphase I or II (if does not split in anaphase I, one cell have 2 extra chromatids, and other missing chromosome) (if does not split in anaphase II, one cell have one extra chromatid and one cell lacking one)

326

denatured

protein unfolded due to pH or temp

327

NADH

the reduced form of NAD+ (nicotinamide adenine dinucleotide). Most common electron carrier in cellular respiration.

328

Somatostatin (SS-gamma cells secrete

PeptideGland: Endocrine Pancreas (SS-gamma cells)Target/Effect: Inhibits many digestive processes

329

What is penetrance?

Percentage of individuals in population carrying allele and actually express its associated phenotype.

330

Division

Plants and Fungi are separated into divisions, not phyla

331

Thermoreceptor

A receptor that responds to changes in temperature.

332

Myofibril

A string of sarcomeres with a skeletal muscle cell (hence smaller than myofiber). Each muscle cell contains hundreds of myofibirils.

333

Myofiber

A skeletal muscle cell, also known as a muscle fiber. Skeletal muscle cells are formed from the fusion of many smaller cells (during development) consequently they are very long and are multinucleate.

334

Lactic acid

Produced in muscle cells from the reduction of pyruvate (under anaerobic conditions) to regenerate NAD+ so that glycolysis can continue. A rise in lactic acid usually accompanies an increase in physical activity.

335

Ligand

The specific molecule that binds to a receptor.

336

Large intestine

The final phase of the digestive tract, also called the colon. The primary funcion of the large intestine is to reabsorb water and to store the feces.

337

Signal sequence

A short sequence of amino aids, usually found at the N-terminus of a protein being translated, that directs the ribosome and its associated mRNa to the membranes of the rough ER where trasnlation will be completed. Signal sequences are found on membrane-boudn proteins, secreted proteins, and proteins destined for other organelles.

338

Secretory phase

The third phase of the uterin (endometrial) cycle, during which the rebuilt endometrium is enhanced with glycogen and lipid stores. The secretory phase is primarily under the controll of progestone and estrogen (secreted from the copus luteum during this time period), adn typically lasts from day 15 to day 28 of the menstrual cycle.

339

Systolic pressure

The pressure measured in the arteries during contraction of the ventricles (during systole).

340

Peripheral chemoreceptors

Receptors in the carotid arteries and the aorta that monitor blood pH to help regulate ventilation rate.

341

Aorta

The largest artery in teh body; the aorta carries oxygenated blood away from the left ventricle of the heart.

342

F1 generation

The first generation of offspring from a given genetic cross.

343

Creatine Phosphate

An energy storage molecule used by muscle tissue. The phosphate from creatine phosphate can be removed and attached to an ADP to generate ATP quickly.

344

Basement membrane

A layer of collagen fibers that separates epithelial tissue from connective tisse (example of epithelial cells in digestive tract) - they are actual connective tissue.

345

Gram-positive bacteria

Bacteria that have a thick peptido glycan cell wall, and no outer membrane. They stain very darkly (purple) in Gram stain.

346

primary transcript

RNA right after transcription from DNA => modified in 3 ways 1) addition of 5' GTP cap 2) removal of introns via snRNPs 3) addition of poly A tail

347

Reduction

to remove oxygen, add hydrogen, or add electrons to a molecule.

348

In pedigrees, how are affected individuals represented? Carriers?

Shaded, half shaded

349

Electrical Synapse

Found in cardiac and visceral smooth muscle cell - composed of gap junctions

350

Is exhalation active?

exhalation is usually PASSIVE but it can be ACTIVE (during strenuous activity, internal intercostal muscle contract)

351

Aqueous humor

A thin, watery fluid found in teh anterior segment of the eye (between the lens and the cornea). THe aqueous humor is constantly produced and drained, adn helps to bring nutrients to the lesn and corena, as well as to remove metabolic wastes

352

Law of Segregation

Mendels' first law. The Law of Segregation states that the two alleles of a given gene will be separate from one another during gamete formation (meiosis).

353

Portal systems

A system of blood vessels where the blood passes from arteries to capillaries to veins, then through a second set of capillaries, and then through a final set of veins. THere are two portal systems in the body, the hepatic portal system and the hypothalamic portal system.

354

A band

The band of the sarcomere that extends the full length of the thick filament. The A band includes regions of thick and thin filament overlap, as well as a region of thick filament only. A bands alternate with I bands to give skeletal and cardiac muscle a striated apperance. The A band does not shorten during muscle contraction.

355

Seondary active transport

Active transport that releies on an established concentration gradient, typically set up by a primary active transporter. Secondary active transport relies on ATP indirectly.

356

Haploid organism

An organism that has only a single copy of its genome in each of its cells. Haploid organisms possess no homolous chromosomes.

357

Distal convoluted tubule

The portion of the nephron tubule after the loop of Henle, but before teh collecting duct. Selective reabsorption and secretion occur here, most notably regulated reabsorption of water and sodium.

358

Anterioir pituitary gland

Also known as the adenohypophysis, the anterior pituitary is made of gland tissue and makes and secretes six different homrones: FSH, LH, ACTH, prolactin, TSH, and growth hormone. The anterior pituitary is controlled b yreleasing and inhibiting factors from the hypothalamus.

359

Reverse transcriptase

An enzyme that polymerizes a strand of DNA by reading an RNA template (an RNA dependent DNa polymerase); used by retrovirus in order to integrate their genome with the host cell genome.

360

Sinoatrial (SA) node

A region of specialized cardiac muscle cells in the right atrium of the heart that initiate the impules of heart contraction; for this reason the SA node is knownas the 'pacemaker' of the heart.

361

Obligate anaerobe

An organism that can only survive in the absence of oxygen (anaerobic metabolism); oxygen is toxic to obligate anaerobes.

362

Fertilization

The fusion of a sperm with an ovum during sexual reproduction. Fertilization typically occurs in the uterine tubes and requires capacitation of the sperm and relase of the acrosomal enzymes. Fertilization is a species-specific process, requiring binding of a sperm protein to an egg receptor.

363

Optic nerve

The nerve extending from the back of teh eyeball to teh brain that carries visual information. The ptic nerve is made up of the axons of the ganglion cells of the retina.

364

Maternal inheritance

Genes that are inherited only from the mother, such as mitochondrial genes (all organelles come only from the ovum).

365

Northern blotting is...

the same as Southern blotting except with RNA

366

primary spermatocyte/oocyte

right after S phase of interphase (in females, division arrested here until puberty) => just before ovulation, primary oocyte undergoes first mitotic division to become secondary oocyte => sperm compels into anaphase II

367

Iris

Colored Circle Portion of the eye that circle opening called pupil - made of circular and radial muscleIn dark environment, sympathetic nervous system contracts the iris which dilate the pupil and allow more light to enterin bright environment, parasympathetic nervous system contracts the circular muscle of the iris, constricting pupil and screening out light

368

Nodes of Raveir

Tiny gap between myelin - action potentials jumps from one node to next and is called saltatory conduction

369

Common bile duct

The duct that carries bile from the gallbladder and liver to the small intestine (duodenum).

370

Diploid organism

An organism that has two copies of its genome it each cell. The paired genomes are said to be homologous.

371

Sex-linked rait

A triat determined by a gen on either the X or Y chromosomes (the sex chromosomes).

372

Slow block to polyspermy

Also known as the cortical reaction, the slow block invovles an increase in intracellular [Ca2+] in the egg, which causes the release of cortical granules near the egg plasma membrane. This results in the hardening of the zona pellucida and its separation from the surface of the egg, preventing the entry of more than one sperm into the egg.

373

Fast block to polyspermy

The depolarization of the egg plasma membrane upon fertilization, designed to prevent the entry of more than one sperm into the egg.

374

function of an enzyme

globular protein that acts as a catalyst by lowering the activation energy and increasing the rate of the reaction; they are not consumed nor permanently altered by the reaction; they do not alter the equilibrium of the reaction

375

Motor (efferent) neurons

signal to muscle or gland – located ventrally – abdomen side of spinal cord

376

Long bones grow by which type of ossification?

endochondroal- (legs, arms)Cartilage first, then bone replaces the cartilage. vs intra= directly from cells NO cartilage template

377

When should a sex-linked gene be suspected in a pedigree?

When only males are affected

378

Cellular respiration equation

C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O

379

During inhalation what are the events the occur?

1. the DIAPHRAM contracts and flattens out, increasing the side of the chest cavity.2. the EXTERNAL INTERCOSTAL MUSCLES contract... moving the rib cage UP and OUT

380

What are the units of recombination frequency?

1 map unit, which = 1% recombinant frequency

381

How are blood types an example of codominance?

IaIa or Iai give Type AIbIb or Ibi give Type Bii gives Type OBUTIaIb gives Type AB, which is a combination (NOT blend) or characteristics of A&B

382

Hypophysis

The pituitary gland.

383

recombinant DNA

spliced DNA

384

Chondrocyte

A mature, cartilage cell.

385

anaerobic respiration

respiration without oxygen

386

Erythropoietin

PeptideGland: KidneyT/E: Bone marrow/ Increase RBC synthesis

387

Semen

An alkaline, fructose-rich fluid produced by three different glands in the male reproductive tract and released during ejaculation. Semen is very nourishing for sperm.

388

Meninges

The protective, connective tissue wrapping of the central nervous system (the dura mater, arachnoid mater, and pia mater).

389

EPSP

Excitatory postsynaptic potential; a slight depolarization of a postsynaptic cell, bringing the membrane potential of that cell closer to the threshold for an action potential.

390

Phospholipid

The primary membrane lipid. Phospholipids consist of a glycerol molecule esterified to two fatty acid chains and a phosphate molecule. Additional, highly hyrohpilic groups are attached to the phosphate, making this molecule extremely amphipathic.

391

Kinase

An enzyme that phosphorylates something else. Kinases are frequently used in regulatory pathways, phosphorylating other enzymes.

392

Phenotype

The physical characterisitcs resulting from the genotype. Phenotypes are usually described as dominant or recessive.

393

operon

operator, promoter, genes => prokaryote

394

Enzyme

A physiological catalyst. Usually proteins although some RNAs have catalytic activity.

395

Glycoproteins

Carbohydrate portions protrude toward outside of cells

396

Microfilament

The cytoskeleton filaments with the smallest diameter. Microfilaments are composed of the contractile protein actin. They are dynamic filaments, constantly beig made and broken down as needed, and are responsible for events such as pseudopod formation and cytokenesis during mitosis.

397

Plasmid

A small, extrachromosomal (outside the genome), circular DNA molecule found in prokaryotes.

398

Edema

Swelling of tissues, sometimes caused by inflammation letting into many white blood cells (decreasing oncotic pressure at the end of the capillaries & not letting as much water back into capillaries & staying in tissues).

399

Intercalcated discs

The division between neighboring cardiac muscle cells. Intercalcated discs include gap junctions, which allow the cells to function as a unit.

400

Insulin

A peptide hormone produced and secreted by the Beta cells of the pancreas. Insulin targets cells in the body, especially the liver and muscle, and allows them to take glucose out of gthe blood (thus lowering blood glucose levels).

401

Innate immunity

General, non-specific protection to the body, including the skin (barrier), gastric acid, phagocytes, lysozyme, and complement.

402

Gametogenesis

The formation of haploid gametes (sperm or ova) via meiosis.

403

Submucosa

The layer of connective tissue directly under the mucosa of an open body cavity.

404

Substrate(s)

The reactants in an enzyme-catalyzed reaction. Substrate binds at the active site of an enzyme.

405

Acetylcholine (Ach)

The neurotransmitter used throughout the parasympathetic nervous system as well as the neuromuscular junction.

406

gene mutation

alteration of DNA nucleotide sequence

407

Krebs

before starting, pyruvate => acetyl CoA; produces 1 ATP, 3 NADH, 1 FADH2 (substrate level phosphorylation)

408

Phosphofructokinase (PFK)

enzyme that catalyzes the phosphorylation of fructose-6-phosphate to form fructose-1-6-biphosphate in third stepp of glycolysis. Main regulatory step in glycolysis. Feedback inhibited by ATP.

409

Endospore

Formed by some gram positive bacteria

410

Cell membrane is ______ly charged compared to the cytosol

positively

411

Tendon

Strong bands of connective tissue that connect skeletal muscle to bone.

412

Formed elements

The cellular elements of blood; erythrocytes, leukocytes, and platelets.

413

Facilitated diffusion

Movement of a hydrophilic molecuel across the plasma membrane of a cell, down its concentration gradient, through a channel, pore, or carrier molecule in the membrane. Because the hydrophilic nature of the molecule, it requires a special path through the lipid bilayer.

414

Urea

A waste product of protein dbreakdown, produced by the liver and relased into the bloodstream to be eliminated by the kidney.

415

Choroid

The darkly pigmented middle layer of the eyeball, found between teh sclera (outer layer) and the retina (inner layer).

416

Channel protein

An integral protein that selectively allows molecules across the plasma membrane. See also entries under 'ion channel', 'voltage-gated channel', and 'ligand-gated channel'.

417

Coccus

A bacteria having a round shape (plural = cocci)

418

Nucleus

An organelle bounded by a double membrane (double lipid bilayer) called the nuclear envelope. The nucleus contains the genome and is the site of replication and transcription.

419

T tubules

Also called transverse tubules, these are deep invaginations of the plasma membrane found in skeletal and cardiac muscle cells. These invaginations allow depolarization of the membrane to quickly penetrate to the interior of the cell.

420

Conjugation

A form of genetic recombination in bacteria in which plasmid and/or genomic DNA is transferred from one bacterium to the toher through a conjugation bridge.

421

Rectum

The final portion of the large intestine.

422

Repolarization

The return of membrane potential to normal resting values after a depolarization of hyperpolarization.

423

Lysozyme

An enzyme that lyses bacterial cell walls. Lysozyme is produced in the end stages of the lytic cycle so that new viral particles can escape their hosst; it is also found in human tears and human saliva.

424

Homologous structures

Physical structures in two different organisms that have structural similarity due to a common ancestor, but may have different functions. Homologous structures arise from divergent evolution.

425

Hematocrit

The percentage of wholeblood made up of erythrocytes The typical hematocrit value is between 40-45%.

426

Microvilli

Microscopic outward folds of the cells lining the small intestine; microvilli serve to increase the surface area of the small intestine for absorption.

427

Spleen

An abdominal organ that is considered part of the immune system. THe spleen has four functions: (1) it filters antigen from the blood (2) it is the site of B cell maturation, (3) it stors blood, and (4) it destroys old red blood cells.

428

Splicing

One type of eukaryotic mRNA processing in which introns are removed from the primary transcript and exons are ligated together. SPlicing of transcripts can be different in different tissues.

429

Spirochete

A bacterium having a spiral shape (plural = spirochetes)

430

Metaphase

The secon phase of mitosis. During metaphase chromosomes align at the center of the ell (the metaphase plate).

431

Oxidation

To attach oxygen, to remove hydrogen, or to remove electrons from a molecule.

432

Autosome

A chromosome that does not determine gender (is not a sex chromosome). Humans have two sex chromsomes and 22 autosomes.

433

glycolipids

same as phospholipids except have one or more carbohydrates attached to glycerol backbone

434

lyase

addition of one substrate to double bond

435

secondary structure

motifs like a-helix and b-pleated sheet

436

Releasing and Inhibiting Factors (Peptides)

Gland: HypothalamusTarget/Effect: anterior pituitary/modify activity

437

Bacterial Flagella

Long hollow rigid helical cylinder made from globular proteins called flagellin and is used for motion

438

All preganglion neurons of ANS and post ganglionic neurons of parasympathetic system – use _________ as a nerotransmiter

Acetyacholine

439

Thecal cells

A layer of cells surroudning the granulosa cells of the follicles in an ovary. Thecal cells help produce the estrogen secreted from the follicle during the first phase of the ovarian cycle.

440

Loose connective tissue

Connective tissue that lacks great amount of collagen or elastic fibers (hence, loose), e.g., adipose tissue and areolar (general connective) tissue.

441

Uterus

The muscular femal organ, in which a baby develops during pregnancy.

442

Thrombus

A blood clot that forms in an unbrokened blood vessel. Thrombi are dangerous they can break free and begin travelin in the bloodstream (become an embolus). Emboli ultimately become stuck in a small vessel and prevent adequate blood delivery to tissues beyond the sticking point, leading to tissue death. A brain embolism cna lead to stroke, a heart embolism to a heart attack, and a pulmonary embolism to respiratory failure.

443

Thin filament

In skeleta and cardiac muscle tissue, a filament composed of actin, tropomyosin, and troponin. Thin filaments are attached to teh Z lines of the sarcomers and slide over thick filaments during muscle contraction.

444

Leak channel

An ion channel that is constitutively open, allowing the movement of teh ion across the plasma membrane according to its concentration gradient.

445

Proprioreceptor

A receptor that responds to changes in body position, such as stretch on a tendon, or contraction of a muscle. These receptor allow us to be consciously aware of the position of our body parts.

446

Restriction endonuclease

A bacterial enzyme that recognizes a specific DNA nucleotide sequence and that cuts the double helix at a specific site within the sequence.

447

Replication bubbles

Multiple sites of replication found on large, linear eukaryotic linear eukaryotie chromosomes.

448

Osteon

The unit of combact bone, also called a Haversian system. Osteons are essentially long cylinders of bone; the hollow center is called the central canal, and is where blood vessels, nervs, and lymphatic vessels are found. Compact bone is laid down around the central canal in rings (lamellae).

449

Oval window

The membrane that separates the middle ear from the inner ear.

450

Parietal cells

Cells found in gastric glands that secrete hydrochloric acid (for hydrolysis of ingested food) and gastric intrinsic factor (for absorption of vitamin B-12).

451

Peptide bond

The bond formed between the carboxyl group of one amino acid and the amino group of another.

452

Polyspermy

The fertilization of an oocyte by more than one sperm. This occurs in some animals, but in humans, blocks to polyspermy exist (the fast block and the slow block) so that only a single sperm can penetrate the oocyte.

453

Appendix

A mass of lymphatic tissue at the befenning of the large intestine that helps trap ingested pathogens.

454

Follicle

A developing oocyte and all of its surrounding (supporting) cells.

455

Cell surface receptor

An integral membrane proteint hat binds extracellular signaling molecules, suchas hormones and peptides.

456

Active transport

The movement of molecules through the plasma membrane against their concentration gradients. Active transport requires input of cellular energy, often in the form of ATP. An example is the Na+/K+ ATPase in the plasma membrane of all cells.

457

insertion/deletion

if not multiple of 3 causes frameshift mutation

458

Competitive Inhibitor

an enzyme inhibitor that competes with substrate for binding at the active site of enzyme. When inhibitor is bound, no product can be made.

459

Define codominance.

When multiple alleles exist for a given gene and more than 1 is dominant.When 2 dominant alleles present, phenotype is result of simultaneous expression of both alleles.

460

somatic nervous system

primarily respond to external environment (sensory and motor functions)its motor only innervates muscle their cell bodies are located on ventral horns of spinal cord and use acetylcholine to synapse directly on effectors (muscle)

461

Microtubules

Contain protein tubulin13 of the filaments (tubulin is normally globular but is straightend to form microtubules) lie alongside each other to form a tubule (spiral appearance is due to two types of tubulin used (alpha and beta))Forms mitotic spindle, flagellum and cilium

462

Renal tubule

The portion of the nephron after the glomerulus and apsule; the region of the nephron where the filtrate is modified along its path to becoming urine.

463

Productive cycle

A life cycle of animal viruses in which the mature viral particles bud from the host cell, acquiring an envelope (a coating of lipid bilayer) in the process.

464

Proximal convoluted tubuel

The first portion of the nephron tubuel after the glomerulus. THe PCT is the site of most reabsorption; all filtered nutrients are reabsorbed here as well as most of the filtered water.

465

Prophase I

The first phase of meiosis I. During prophase I the replicated chromosomes condense, homologous chromsomes pair up, crossing over occurs between homologous chromosomes, the spindle is formed, and the nuclear envelope breaks apart into vesicles. Prophase I is the longest phase of meiosis.

466

Cortex

The outer layer of an organ, e.g. the renal cortex, the ovarian cortex, the adrenal cortex, etc.

467

Sertolli cells

Cells that form the walls of the seminiferous tubules and help in spermatogenesis Sertoli cells are also called susenacular cells.

468

Skeletal muscle

Muscle tissue that is attached to the bones. SKeletal muscle is striated multinucleate, and under voluntary control.

469

Auditory tube

The tube that connects the middle ear acity with the pharynx; also known as the Eustachian tube. Its fucntion is to equalize midle ear pressure with atmospheric pressure so that pressure on boths sides of the tympanic membrane is the same.

470

Retrovirus

A virus with an RNA genome (e.g. HIV) that undergoes a lysogenic life cycle in a host with a double stranded DNA genome. In order to integrate its genome with the host cell genome, the virus must first reverse trasncribe its RNA genome to DNA.

471

Allele

A version of a gene. For example, the gene may be for eye color, and the allels include those for brown eyes, those for blu e eyes, those green eyes, etc. At most, dploid organsims can posses only two alleles for a given gene, one on each of the two homologous chromosomes.

472

Vagus nerves

Cranial nerve pair X. The vagus nerves are very large mixed nerves (They carry both sensory input and motor input) that innervate virtually every visceral organ. They are especially important in transmitting parasympathetic input to the heart and digestive smooth muscle.

473

Integral membrane protein

A protein embedded in the lipid bilayer of a cell. These are typicallly cell surface receptors, channels, or pumps.

474

Pyruvate dehydrogenase complex

a group of three anzymes that decarboxylates pyruvate, creating an acetyl group and carbon dioxide. The acetyl group is then attached to coenzyme A to produce acetyl-CoA, a substrate in Krebs cycle. In the process, NAD+ is reduced to NADH. The second stage of cellular respication.

475

Fungal Growth Phase

Consists of tangled mass (called mycelium) of multiple branched threadlike structures called hyphaeHaploid life cycle predominates most of the timeHaploid spores give rise to new mycelia in sexual reproduction

476

Connective tissue

One of the four basic tissue types in the body (epithelial, connective, muscle, and nervous). Connective tissue is a supportive tissue consisting of a relatively few cells scattered among a great deal of extracellular material (matrix), and includes adipose tissue (fat), bone, cartilage, the dermis of teh skin, tendons, ligaments, and blood.

477

Long bone

The most common class of bone in the body, long bones have a well-defined shaft (the diaphysis) and two well-defined ends (the epiphyses).

478

Ovarian cycle

The 28 days of the menstrual cycle as they apply to events in the ovary. The ovarian cycle has three subphases: the follicular phase, ovulation, and the luteal phase.

479

Epithelial tissue

One of the four basic tissue types in the body (epithelial, connective, muscle, and nervous). Epithelial tissue is a lining and covering tissue (e.g. skin, the lining of the stomach and intestines, the lining of the urinary tract, etc. ) or a glandular tissue (e.g. the liver, the pancreas, the ovaries, etc.)

480

triacylglycerols (triglycerids, fats, oils)

have 3 carbon backbone called glycerol attached to three fatty acids

481

Ribosomes:

Prokaryotes - 30S and 50S - 70S combined

482

# of subunits

Eukaryotes - 40S and 60S - 80S combined

483

Lymphatic system

A set of vessels in the body that runs alongside the vessels of the circulatory system. It is a one-way system, with lymphatic capillaries beginning at the tissues and ultimately emptying into the large veins near the heart. It serves to return excess tissue fluid (lymph) to the circulatory system, and filters the fluid through millions of white blood cells on its way back to the heart.

484

What is a dihybrid cross?

Cross where parents differ in 2 traits

485

If the F1 generation of a PP x pp cross is self-crossed, what will be the F2 genotypic and phenotypic ratios?

Genotype: 1:2:1 (1PP:2Pp:1pp)Phenotype: 3:1 (3 purple:1 white)

486

If gene X and gene Y have a recombinant frequency of 8%, and gene X and gene Z recombine 12% of the time, what are the possible distances between genes Y & Z?

4 or 20 map units

487

G Cell

Secretes gastrin

488

DNA polymerase

Removes nucleotidesautomatic proofreaderrepairs mismatch nucleotidesTherefore, DNA replication is fast and accurate

489

cortisol

made: adrenal cortexeffects: stimulates gluconeogenesis in liver, degrades adipose tissue for energy, diminishes immune response

490

NUCLEIC ACID

complex, high-molecular-weight biochemical macromolecule composed of nucleotide chains that convey genetic information like DNA and RNA

491

cellulose

glucose polymer w/beta linkages, found in plants. not digestable by animals.

492

glucagon

made: pancreaseffects: raise blood glucose levels, by promoting gluconeogenesis and glycogenolysis in liver. Also breaks down adipose tissue. (fat)

493

Progesterone

made: ovarieseffect: prepares and maintaines uterus for pregnancy

494

CONTROL PROTEINS

activate or inactivate enzymes

495

CONJUGATED PROTEINS

proteins with non-proteinaceous groups

496

Translation

Process of protein synthesis directed by mRNAnucleus -> cytosol (mRNA)anticodon (tRNA)makes ribosome (rRNA)

497

phospholipids

glycerol backbone, 2 fatty acids, phosphate group. Amphipathic and used to build membranes.

498

Placenta hormones

HCG, (Estrogens, Progesterone... in addition to ovaries).

499

pancreas

located near kidneyboth endo and exocrine gland.releases insulin and glucagon.

500

inflammation

dilation of blood vessels, increased capillary permeability, swelling of tissue cells, migration of macrophages and granulocytes to inflamed area. Impedes spread of infection.