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1

Sexual Reproduction

offspring arise from two parents and a mixture of genes are inherited from both, offsprings will have better chance of survival of effects of mutations

2

Asexual Reproduction

produces genetically identical copies of a single parent (clones)

3

Mitosis

somatic cells, purpose of growth, repair and replace, diploid to diploid

4

Meiosis

division of specialized cells that form reproductive cells known as gametes. A diploid cell into 4 haploid gametes. Nuclear division, halves chromosome number

5

2 Haploid Gametes fuse to produce

zygote

6

Zygotes are

diploid 2n

7

Gametes do not__, they ___

divide, produced by germ cells by meiosis

8

How many chromosomes in human somatic cell and how many pairs

46;23

9

Mitosis ___ chromosome number. Meiosis ___ chromosome number

maintain; reduce.

10

Haploid

single set of chromosome (n)

11

Diploid

double set of Chromosome (2n)

12

Genes

regions in an oragnism's DNA that encode information about heritable traits. Pairs on homologous chromosomes.

13

Alleles

Different versions of the same gene.

14

DNA is replicated

Once

15

Meiosis 1

Diploid germ cell replicated its chromosome and form tetrad (pairs of duplicated homologous chromosomes); each duplicated homologous chromosome is separated from its partner

16

Meiosis II

two haploid cells cells divide, sister chromatids are separated (like in mitosis)

17

Stages of Meiosis I

Prophase: homologous chromosomes condense, pair up, and swap segments. Aka crossover stage
Metaphase: Chromosomes line up
Anaphase: Chromosomes separate
Telophase: A new nuclear envelope cause so two haploid nuclei form.

18

Stages of Meiosis II

Prophase II: the chromosomes condenses with no dna replication
Metaphase II: chromosomes align
Anaphase II: Sister chromatids separate
Telophase II: 4 haploid cells

19

Crossover

happens in proffer I, helps with genetic variability. mixture of both parents.

20

random assortment produces

2^23 possible combinations of homologous chromosome

21

Sporophytes

Diploid bodies with specialized structures that form spores (haploid cells) that give rise to gametophytes through mitosis

22

Gametophytes

A multi-celled haploid body inside which on ore more gametes form

23

fertilization

fusion of two haploid gametes (sperm and egg) resulting in a diploid zygote

24

Genes occur in pairs of

homologous chromosomes

25

Gregor Mendel

Breeding garden pea plants

26

Characters

heritable features that vary among individuals

27

Traits

variants for a character

28

Genes

Discrete heritable units of information for traits

29

Alleles

Alternative forms of a gene

30

Each gene has a specific ___on a chromosome

locus

31

How many chromosomes do diploid cells have

2 pairs of homologous chromosomes

32

Genotype

Particular set of allies that an individual carries
(Bb, BB, bb)

33

Homozygous

Two identical alleles of a gene is homozygous for that gene

34

Heterozygous

An individual with non-identical alleles of a gene

35

Phenotype

Observable traits such as color

36

Mutated genes are

new alleles whether or not it affects a phenotype

37

True breeding

individual that is homozygous for a particular trait; the same trait is produced over many generations. AA or aa

38

Hybrid

the heterozygote offspring of a cross between two individuals that breed true for different forms of a trait. Aa

39

Dominant and Recessive Alleles

Dominant is shown in a heterozygote phenotype and recessive is not

40

Genotypes of :
Homozygous dominant
Heterozygous
Homozygous recessive

AA; Aa; aa and they only have 2 phenotypes

41

Probability

A measure of the chance that a particular outcome will occur

42

Punnett square

a grid used to calculate the probability of genotypes and phenotypes among offspring of various crosses

43

Testcross

method of determine if an individual is heterozygous or homozygous dominant (BB x bb)

44

Monohybrid Cross

between two individuals that are heterozygous for a certain character. crossing of two true-breeding individuals resulting in heterozygote offspring and they are hybrids which are represented in the first filial generation. Then those hybrids are crossed with each other to produce the second filial generation

45

Mendel's Law of Segregation

Differing traits in organisms result from pairs of genetic factors that separate during gamete formation such that each gamete receives only one of the two factors.

46

Dihybrid

16 results of genotypes, and phenotype ratio is 9:3:3:1

47

Mendel's Law of Independent Assortment

during gamete formation, members of one pair of 'genetic factors' are distributed into gametes independently of other pair

48

Law of Segregation Modern

Different traits are the result of the separation of pairs of alleles on homologous chromosomes into discrete gametes during meiosis

49

Law of Independent Assortment Modern

Each pair of alleles is sorted into gametes independently of other pairs during meiosis; we now know that this law applies when the genes are located on different pairs of homologous chromosomes

50

Linkage group

all genes on one chromosome
genes are passed on together

51

Linked genes

very close together; crossing over rarely occurs between them

52

Codominance

two non-identical alleles of a gene are both fully expressed in heterozygotes, so neither is dominant or recessive

53

Multiple Allele System

genes with three or more alleles in a population
ex. blood types

54

Incomplete Dominance

one allele is not fully dominant over its partner, and the heterozygous offspring is a mix

55

Epistasis

Two or more gene products influence a trait, one gene product suppresses the effect of another (dog color)

56

Bell Curve

When continuous phenotypes are divided into categories and plotted as a bar chart.

57

genotype + environment=

phenotype

58

Are phenotypes qualitative

yes

59

Mendelian Genetics

Characters are controlled by a single gene
Alleles exhibit a complete dominance relationship
Phenotypes are qualitative

60

Pleiotropy

Single gene affecting many traits

61

Epigenetics

heritable changes NOT caused by change in DNA sequence

62

Genetic abnormalities

rare version of trait, not life-threateneing

63

Genetic disorder

does cause health problems, may be life threatening

64

Geneticists

study inheritance pattern in humans by tracking these genetic abnormalities and disorders through families

65

Pedigree

used to determine the probability that future offspring will be affected by a genetic abnormality or disorder

66

An allele is inherited in an autosomal dominant pattern if

if the trait it specifies appears in people with homozygous dominant and heterozygous genotypes

67

An allele is inherited in an autosomal recessive pattern if

if the trait it specifies appears only in people with homozygous recessive genotypes

68

Achondroplasia

Homozygous dominant individuals do not survive long enough to reproduce

69

Huntington's Disease

Symptoms often do not develop until after 30 years of age
An affected individual may have already passed on the allele to offspring

70

Hutchinson-Gilford Progeria

Most individuals with this disease do not survive long enough to reproduce

71

Autosomal Recessive Inheritance

Skips generations, two recessive alleles, so heterozygotes do not have trait.

72

Albinism

Depending on which gene(s) are affected, absence or low levels of melanin may affect pigmentation of skin, hair, eyes

73

Autosomes and Sex Chromosomes pairs

22 pairs of autosomes(homologous) and 1 pair of sex chromosomes (non-homologs)

74

X-linked Disorders

inherit in a recessive pattern because dominant X chromosomes tend to be lethal in male embryos, only homozygous females have this disorder.
an ex. is color blindness

75

all new alleles arise by

mutation

76

duplication

DNA sequence that are repeated two or more times, duplication may be caused by unequal crossover in prophase

77

Deletion

Loss of some portion of a chromosome, usually causes serious or lethal disorders

78

Inversion

Part of the sequence of DNA becomes oriented in the reverse direction with no molecular loss

79

Translocation

If chromosome breaks, the broken part may get attached to a different chromosome, or to a different part of the same one.

80

Polyploid

they have three or more complete sets of chromosomes

81

Trisomy 21

down syndrome

82

Karyotype

arrangement of chromosome in pairs 23

83

Changes in sex chromosome number may

impair learning or motor skills or be undetected

84

Stem Cells

divide to produce more stem cells
OR
differentiate into specialized cells

85

Totipotent

embryonic stem cells develop into a individual

86

Embryonic Stem Cells (hESCs)

hold the potential to repair tissues that are normally not regenerated in the adult body

87

Cell Junctions

Connects cells, tights junctions (prevent fluid movement between cells), gap junctions(channel connects cytoplasm between cells) and adhering junctions(connect cels together)

88

Hierarchical Level

Atoms
Molecules
Organelles
Cells
Tissues
Organs
Organ System
Organism

89

Epithelial tissue

covers body surfaces and lines the internal cavities such as the gut

90

connective tissue

holds body parts together and provides structural support

91

Muscle tissue

moves the body or its parts

92

Nervous tissue

detects stimuli and relays signals

93

extracellular fluid

surrounds cells, provides them with nutrients, and collects cellular waste

94

Plasma

fluid portion of blood

95

Generation evolution genes

genes that will best help an individual survive and reproduce in their environment are preferentially passed on

96

Diffusion is only efficient through

short distances

97

Evolution modifies

existing structures

98

Epithelium (epithelial tissue)

A sheet of cells that covers the body's outer surface and lines internal ducts and cavities

99

Basement membrane

A layer of ECM (extracellular matrix) that is synthesized and secreted by the cells themselves

100

Simple squamous epithelium

lines blood vessels, the heart, and air sacs of lungs. allows substances to cross by diffusion

101

simple cuboidal epithelium

lines kidney tubules, ducts of some glands, reproductive tract. Functions in absorption and secretion, movement of materials

102

simple columnar epithelium

lines some airways, part of the gut. Functions in absorption and secretion, protection.

103

Cells that move substances across the surface of an epithelium have___

cilia

104

Glands are derived from_____. What does it do?

Epithelium. Secrete products destined for extracellular function

105

Exocrine Glands

ducts; external such as tears and internal such as enzymes to small intestine

106

Endocrine Glands

no ducts; cell products are released by interstitial fluid picked up by blood vessels for delivery to target hormones

107

Connective tissues

consist of cells and the extracellular matrix that is synthesized and secreted by these cells.
Connects body parts and provides structural and functional support.
Cartilage, bone, tissue and blood

108

Loose connective tissue

fibroblasts secrete ECM consisting of complex carbohydrates and protein fibers dispersed widely through the matrix

109

Dense Connective tissue

w/ dense collagen fibers. Ligaments (bone to bone) and tendons (muscle to bone)

110

cartilage

rubbery extracellular matrix, supports and cushions bones

111

adipose tissue

fat filled cells, stores energy, cushions and protect organs

112

Bone

rigid support, muscle attachment, protection , mineral storage, blood production

113

blood

connective tissue because its cells and platelets descend from stem cells in bone

114

ATP provides energy that fuels muscle ____

contractions

115

Skeletal muscle tissue

moves the skeleton (voluntary)
long, started cells with many nuclei

116

Cardiac muscle tissue

heart muscle (involuntary)
striated cells with single nuclei

117

Smooth muscle tissue

In walls of hollow organs (involuntary), no striations, single nuclei

118

nervous tissue

detects changes in the internal or external environment, integrates info, and controls the activity of muscle and glands

119

Nervous tissue consist of specialized

signal cells (neurons) and cells that support them (neuroglial cells)

120

Neurons

excitable cells with long cytoplasmic extensions; they send an receive electrochemical signals

121

3 types of neurons

sensory neurons, interneurons and motor neurons which relay command from brain and spinal cord to muscle and glands

122

Neuroglia (neuroglial cells)

keep neurons in position and provide them with nutrients. They wrap around single sending cytoplasmic extensions of motor neurons and act as insulation that speeds the rate at which signals travel

123

integumentary system

protects body from pathogens, injuries; controls temp, excretes certain waste

124

Nervous system

detects external and internal stimuli; controls and coordinates the responses to stimuli. Integrates organ system.

125

Muscular system

moves body and is internal parts; maintains posture; generates heat by increases in metabolic activity

126

skeletal system

supports and protects body parts; provides muscle attachment sites; produces red blood cells; stores calcium, phosphorus

127

Circulatory system

rapidly transports many materials to and from interstitial fluid and cells; helps stabilize internal pH and temperature

128

Endocrine system

Hormonally controls body functions

129

Lymphatic system

collects and returns some tissue fluid to the bloodstream; defends the body against infection and tissue damage

130

Digestive system

Ingests food and water; mechanically, chemically breaks down food and absorbs small molecules into internal environment; eliminates food residues

131

urinary system

maintains volume and composition of internal environment; excretes excess fluid and waste

132

reproductive system

females: produce eggs
Male: Transfer sperm to female

133

integumentary system

consists of skin, connective and adipose tissue. Skin helps conserve water. Helps control internal temperature

134

Outer epidermis vs deeper dermis

outer contains keratinocytes and inner contains nerves, blood and lymph vessels, hair follicles and glands

135

epidermis

a stratified squamous epithelium with adhering junction and no extracellular matrix

136

dermis

consists primarily of dense connective tissue with elastin and collagen fibers.
ex. blood vessels, lymph vessels, sensory receptors, sweat glands, sebaceous glands and hair follicles

137

sensory receptor

a structure that detects a specific stimulus and sends sensory information to the brain

138

Negative feedback

process in which a change causes a response that reverses the change
ex. when you get hot you sweat
stimulus--sensory receptors--brain--muscle/gland--response

139

urinary system

filters water, metabolic wastes and toxins out of the blood, and reclaims water

140

kidneys

paired, excretory organs that filter blood and adjust level of solutes

141

marine body fish

hypotonic to its environment

142

freshwater fish

hypertonic to its environment

143

kidneys filter blood and form

urine

144

tight junctions

prevent fluid movement between cells

145

adhering junction

connects cells together

146

interstitial fluid

fluid in spaces between cells

147

coelom

human are bilateral and have a lined body cavity

148

Urine flows through ___ into a ____ that stores it

ureters; bladder

149

Urine flows out the body through the _____

urethra

150

nephron

browman's capsule
proximal tube
loop of henle (water out, sodium in)
distal tubule (water, sodium out)

151

blood is delivered to a cluster of _____ inside a bowman's capsule; fluid is ___ ___ of the blood vessels and filtered

capillaries (glomerulus); forced out

152

Glomerular filtration

first step in urine formation; occurs in Bowman's capsule

153

Tubular reabsorption

returns most water and solutes to the blood

154

Renal Medulla

fliters in kidneys

155

Tubular secretion

movement of un-needed substances from the blood of the peritubular capillaries into the filtrate (to excrete as urine); occurs along nephron's tubules

156

Concentrating Urine

flows down loop of Henle

157

Hypothalamus and Thirst

Hypo notifies you when you are thirsty by a hormone

158

Antidiuretic hormone (ADH)

released by the pituitary when sodium level rise.

159

Aldosterone

released by the adrenal cortex, increase salt reabsorption in collection ducts; water follows by osmosis; urine is concentrated

160

Renin

converts angiotensinogen to angiotensin I, converted to angiotensin II, which acts on the adrenal cortex to secrete aldosterone
sits on top of kidney
leads to aldosterone

161

reabsorption

returns most water and solute to blood

162

secretion

unneeded stuff released

163

Normal pH extracellular fluid

7.35-7.45

164

buffer system

minimizes pH changes by reversibly binding and releasing H+

165

Kidneys adjust blood pH by ___

H+ secretion; excess H+ leaves the body in urine. only organ that can release hydrogen ion

166

Ectotherms

body temp changes with environment, regulating by altering position, not metabolism (fish, amphibians and reptiles)

167

Endotherms

body temp maintained by metabolic heat (birds and mammals)

168

Heterotherms

can maintain or decrease core temp (some birds and mammals)

169

Change in body heat =

heat produced+heat gained -heat lost

170

Thermal radiation

heat is emitted into space surrounding an object

171

Conduction

heat is transferred by direct contact

172

convection

heat is transferred by movement of air or water by a breeze

173

evaporation

heat is lost when liquid is converted to a gas, sweat.

174

Hypothalamus functions like thermostat to______

maintain core temp via neg feedback

175

Fever

an increase in body temp regulated by hypothalamus, in response to infection

176

Torpor

a period of decreased metabolic rate and activity in response to low food availability

177

Hibernation

a period of dormancy during the cold season where animal is inactive

178

Estivation

desert lizards become dormant, spent season burrow deep in soil

179

sensory neurons

detect stimuli and signal interneurons or motor neurons
Have an axon with one end that responds to stimuli

180

interneurons

process information from sensory neurons and send signals to motor neurons
many dendrites and one axon

181

motor neurons

control muscle and glands
signals to motor neurons many dendrites and one axon

182

Central nervous system

brain and spinal cord

183

Peripheral nervous system

nerves from the CNS to the rest of the body and from the body to CNS
autonomic nerves and somatic nerves control different organs of the body

184

Nerve

consists of nerve fibers bundled inside a sheath of connective tissue

185

autonomic nerves

regulative body's internal state; glands, cardiac muscle...

186

Somatic nerves

monitor body's position and external conditions; they control skeletal muscle

187

Dendrites

receive info from other cells

188

Axons

send chemical signals to other cells

189

Mylein sheath

helps move neuron move faster

190

Voltage gate

postive feedback and allows more sodium to open

191

Membrane potential

negatively charged proteins and active transport of Na+ and K

192

Resting membrane potential

an unstimulated neuron. sodium is concentrated higher outside of the cell and potassium is higher inside cell

193

Action Potential

travels along axon to terminal

194

Graded potential

slight shift in the voltage difference across the neuron's membrane

195

threshold potential

when stimulus in neuron's trigger zone reaches, sodium channels open

196

Once threshold level is reached

membrane potential always rises to the same level as action potential peak (all or nothing response)

197

Outward diffusion of K+

causes membrane potential to decline to a bit below its resting value in a small area

198

Action potential is

self propagating- sodium ions diffuse to the adjoining region of the axon, triggering sodium gates one after another

199

Action can only move

one way, toward axon terminals- a brief refractory period after sodium gates close prevents the signal from moving backwards

200

Neuron's membrane potential over time:

resting level--threshold level--peak is action potential

201

Synapse

is the region where an axon terminal send chemical signal to a neuron, muscle fiver or gland cell (postsynaptic cel)

202

Neuromuscular junction

the synapse between a motor neuron and a skeletal muscle fiber

203

Chemical synapse

action potential trigger release of signaling molecules (neurotransmitters) from axon terminals

204

Release of neurotransmitters from vesicles of the presynaptic neuron requires ____

Calcium ions

205

Myelin sheath

increases the transmission speed of action potential
wraps around neuron

206

Somatic nervous system

conducts information about the environment to the central nervous system (involuntary)
controls skeletal muscles (voluntary)

207

Autonomic nervous system

conducts signals to and from internal organs glands

208

Sympathetic neurons

active in stress or danger (fight or flight response)

209

Parasympathetic neurons

active in time of relaxation

210

Spinal cord

connects peripheral nerves with the brain

211

Central nervous system are made of

brain and spinal cord

212

Meninges

three membranes that cover CNS

213

Cerebrospinal fluid

fills central canal

214

Dorsal roots

sensory info

215

Ventral roots

motor signals

216

Reflex

automatic response to a stimulus, a movement or other action that does not require thought

217

Organizations of brain

forebrain, midbrain, hindbrain.

218

Weight of human brain

3 pounds or 1240 grams

219

Medulla Oblongata

connects the spinal cord

220

Pons

adjoins the medulla, it affects breathing and has connections to midbrain

221

Cerebellum

balance, motor skills and language

222

Brain stem

reflex behaviors

223

Cerebrum

main processing center. thought and language.

224

Corpus callosum

signals two hemispheres of cerebrum

225

Thalamus

receives sensory signals, sorts them and sends them to proper region of the cerebral cortex

226

Hypothalamus

center of homeostatic control of internal environment. Regulates thirst, appetite, sex and temp

227

Cerebral cortex

outermost gray matter, controls voluntary activity, sensory perception, abstract thought, language and speech

228

4 lobes of brain

frontal, temporal, occipital and parietal

229

Primary motor cortex

controls skeletal muscles

230

primary somatosensory cortex

front of the parietal lobe receives sensory input form the skin and joints

231

limbic system

governs emotion, memory and and gratifying behaviors.
includes: hypothalamus, hippocampus, amygdala, and cingulate gyrus

232

emotional state influences

long term memory

233

Neuroglial cells

act as framework that holds neurons in place

234

Action Potential speed

120 m/s vs 10m/s for non myelinated nerves

235

Oligodendrocytes

make myelin sheaths

236

microglia

have immune sytem functions

237

astrocytes

stimulate formation of the blood brain barrier

238

ependymal cells

line brain cavities

239

Hormones

internal secretions carried by the blood that influence the activities of specific body organs

240

Hormone action

signal is transduce (charged into a form that affects target cell behavior

241

hypothalamus is the main center for control of

the internal environment – it connects structurally and functionally with the pituitary gland

242

pituitary gland

The posterior lobe secretes hormones made in the hypothalamus
The anterior lobe makes its own hormones

243

Antidiuretic hormone (ADH)

affects certain kidney cells
Manufactured by hypothalamus, stored and released by posterior pituitary gland. Controls water

244

Oxytocin (OT)

triggers muscle contractions during childbirth

245

Releasing hormones

encourage secretion of hormones by target cells

246

Inhibiting hormones

reduce secretion of hormones by target cells

247

anterior pituitary produces hormones of its own:

Growth hormone (GH)Thyroid-stimulating hormone (TSH

248

Acromegaly

bones getting bigger as you age

249

The thyroid gland

located at the base of the neck, regulates metabolic rate

250

Parathryoids

regulate calcium levels
Needed for bone

251

adrenal cortex

secretes steroid hormones and small amounts of sex hormones

252

cortisol

affects metabolism and the stress response

253

adrenal medulla

contains specialized neurons of the sympathetic division that release epinephrine and norepinephrine, which stimulate the fight-flight response

254

Ovaries produce

estrogens and progesterone

255

hypothalamus and anterior pituitary control secretion of

sex hormones by gonads

256

The hypothalamus produces gonadotropin-releasing hormone (GnRH)

which causes the anterior pituitary to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH