Biology Flashcards
(413 cards)
1
Q
Describe cell theory.
A
The cell theory states that all living things are composed of cells; cells are the basic functional unit of life; cells arise only from pre-existing cells; and cells carry their genetic information in the form of DNA.
2
Q
Name the two distinct groups into which all cells can be categorized?
A
All cells can be categorized as either prokaryotes or eukaryotes.
3
Q
What is the key differentialting criterion between prokaryotic and eukaryotic cells?
A
Eukaryotic cells have membrane-bound organelles; however, prokaryotic cells do not.
4
Q
T/F, bacteria and viruses are examples of prokaryotic cells.
A
False, bacteria are prokaryotic while viruses are non-living acellular structures.
5
Q
Describe bacterial DNA?
A
Bacterial DNA consists of a single circular chromosome.
6
Q
What is a plasmid?
A
A plasmid is a smaller extrachromosomal ring of DNA sometimes found in bacteria. It replicates independently of the bacterial chromosome.
7
Q
T/F, bacteria contain ribosomes?
A
True, but prokaryotic ribosomes are smaller than eukaryotic ribosomes.
8
Q
Name the components of a typical bacterial cell?
A
Cell wall, cell membrane, cytoplasm, ribosomes, flagella, and DNA.
9
Q
Where does respiration occur in the bacterial cell?
A
The cell membrane is the site of respiration in bacteria.
10
Q
T/F, all multicellular organisms are composed of eukaryotic cells?
A
True.
11
Q
Which type of eukaryotic cells haave a cell wall?
A
Plant cells and fungal cells have a cell wall.
12
Q
What is cytosol?
A
Cytosol is the fluid component of the cytoplasm.
13
Q
What are the primary components of the cytoskeleton?
A
The primary components of the cytoskeleton are microtubules, microfilaments, and intermediate fibers.
14
Q
Define the fluid mosaic model?
A
The fluid mosaic model states that a cell membrane consists of a phospholipid bilayer with proteins embedded throughout.
15
Q
Is the interior of a cell memebrane hydrophilic or hydrophobic?
A
The interior of a cell membrane is hydrophobic.
16
Q
What are the very tips facing outward called on the phospholipid bilayer?
A
Polar heads.
17
Q
What are the inner tails of the phospholipid bilayer called?
A
Non-polar tails.
18
Q
What are the function of transport protein?
A
A transport protein helps move polar molecules and certain ions across the cell membrane.
19
Q
What is a memebrane receptor?
A
A membrane receptor is a protein (or glycoprotein) that binds to molecules in the extracellular environment.
20
Q
Can small polar and non-polar molecules easily cross the cell membrane?
A
Yes, because of their size, small polar and non-polar molecules can easily traverse the cell membrane.
21
Q
How does a large charged molecule cross the cell memebrane?
A
A large charged particle usually crosses the cell membrane with the help of a carrier protein.
22
Q
T/F, the nucleus is surrounded by a single-layered memebrane?
A
False, the nuclear membrane is double-layered.
23
Q
How is material exchanged between the nucleus and the cytoplasm?
A
The nuclear membrane contains nuclear pores that selectively allow for the exchange of materials.
24
Q
What is a histone?
A
A histone is a structural protein complexed with eukaryotic DNA to form a chromosome.
25
What is the function of the nucleolus?
The nucleolus synthesized ribosomal RNA (rRNA).
26
What is the function of a ribosome?
A ribosome is the site of protein translation (assembly) during protein synthesis.
27
What is the general function of the endoplasmic reticulum?
Endoplasmic reticulum is involved in the transport of material throughout the cell.
28
What is the function of smooth endoplasmic reticulum (smooth ER)?
Smooth ER is the site of lipid synthesis and poison detoxification, and it is involved in protein transport within the cell.
29
What is the function of rough endoplasmic reticulum (RER)?
RER serves as an attachment point for ribosomes, which functions in protein synthesis for membrane bound proteins and proteins to be excreted from the cell.
30
T/F, proteins synthesized by RER are secreted directly into the cytoplasm?
False, they are secreted into the cisternae of RER and then sent to smooth ER, where they are secreted into vesicles.
31
What is the function of the Golgi apparatus?
The Golgi apparatus receives vesicles from smooth ER, modifies them, and repackages them into vesicles for distribution.
32
What happens to a secretory vesicle after it is released from the Golgi apparatus?
A secretory vesicle from the Golgi fuses with the cell membrane to release its contents via exocytosis.
33
T/F, vesicles and vacuoles are membrane-bound sacs involved in transport and storage of cellular materials?
True.
34
What is a lysosome?
A lysosome is a membrane-bound vesicle that contains hydrolytic enzymes involved in intracellular digestion.
35
T/F, lysosomes fuse with endocytotic vesicles and help digest their contents?
True.
36
How does the pH in the interior of a lysosome compare with the pH in the rest of the cell?
The interior of a lysosome is acidic and therefore has a lower pH than the rest of the cell.
37
What would happen if a lysosome released its contents into the cytoplasm?
The hydrolytic enzymes of the lysosome would digest the organelles and kill the cell. This process is known as autolysis.
38
What is the function of peroxisomes?
Peroxisomes make hydrogen peroxide and digest fats into smaller molecules.
39
What is the funciton of mitochondria?
Mitochondria are the sites of aerobic respiration and supply most of the cell's energy.
40
T/F, mitochondria have their own circular DNA?
True.
41
Do mitochondria replicate in a manner similar to a cell's other organelles?
No, they replicate via binary fission.
42
T/F, mitochondria and cholorplasts are similar structures and both are considered to be semi-autonomous?
True.
43
What is the function of a cell wall?
A cell wall protects the cell from external stimuli and desiccation.
44
What is the function of centrioles?
Centrioles are involved in spindle formation during cell replication. They are found only in animal cells.
45
What is a centrosome?
The centrosome is the region of a cell that contains the centrioles.
46
What is the function of the cytoskeleton?
The cytoskeleton gives mechanical support, maintains the cell's shape, and functions in motility.
47
What is the function of microtubules?
Microtubules maintain cell shape, form the spindle apparatus and provide tracks along which organelles can move.
48
T/F, cilia and flagella are specialized arrangements of microfilaments and function in cell motility?
False, while cilia and flagella do function in cell motility, they are composed of microtubules.
49
T/F, microfilaments are solid rods of actin and are involved in cell movement and cell wall support.
True.
50
T/F, simple diffuction is a passive process that requires energy?
False, simple diffusion is a passive process and therefore DOES NOT require energy.
51
Define osmosis.
Osmosis is the simple diffusion of water from a region of lower solute concentration to a region of higher solute concentration.
52
What would happen to a cell if it were put in a hypertonic solution?
A hypertonic solution would cause water to flow out of a cell and cause the cell to shrink.
53
T/F, a hypotonic solution will cause water to flow into a cell, causing it to swell?
True.
54
Define isotonic.
A medium and a cell are said to be isotonic when the solute concentrations of the medium and the cell are equal.
55
Define facilitated diffusion.
Facilitated diffusion is the net movement of dissolved particles down their concentration gradient with the help of carrier molecules.
56
T/F, facilitated diffusion requies energy?
False, all forms of diffusion, including facilitated diffusion, are passive processes.
57
Define active transport.
Active transport is the net movement of dissolved particles against their concentration gradient with the help of carrier molecules. This process requires ATP.
58
T/F, active transport requires energy?
True.
59
What is endocytosis?
Endocytosis is a process in which the cell membrane invaginates, forming an intracellular vesicle containing extracellular medium.
60
What is exocytosis?
Exocytosis is a process in which a vesicle within the cell fuses with the cell membrane and releases its contents to the extracellular medium.
61
What is the difference between pinocytosis and phagocytosis?
Pinocytosis is the endocytosis of liquids and small particles, whereas phagocytosis is the endocytosis of large particles.
62
What are the four basic types of tissue found in the body?
The four basic types of tissue found in the body are: epithelial, connective, nervous, and muscle.
63
What are the componenets of a virus?
A protein coat and nucleic acid.
64
What kinds of nucleic acid are found in viruses?
Single- or double-stranded DNA or RNA.
65
T/F, viruses are obligate intracelluar parasites?
True.
66
What is a bacteriophage?
A bacteriophage is a virus that infects bacteria only.
67
What is the genetic material of a virus?
The genetic material of a virus can be DNA or RNA.
68
How do enzymes speed up a reaction?
Enzymes are protein catalysts that accelerate a reaction by reducing the amount of activation energy required.
69
T/F, enzymes get used up during the course of a reaction?
False, enzymes are catalysts and therefore don't get used up during the course of a reaction.
70
T/F, enzymes are very selective in the reactions they catalyze?
True.
71
What is substrate?
A substrate is a molecule upon which an enzyme acts.
72
What is an active site?
An active site is the area of an enzyme to which a substrate binds.
73
What is the lock and key theory?
The lock and key theory states that an enzyme and its corresponding active site are exactly complementary.
74
T/F, the induced fit hyposthesis holds that an enzyme causes a conformational change in its corresponding active site to facilitate substrate binding.
True.
75
What is a cofactor?
A cofactor is a nonprotein molecule that is incorporated into an enzyme and is required for proper functioning.
76
What is the difference between an apoenzyme and a haloenzyme?
An apoenzyme is an enzyme without its corresponding cofactor. A holoenzyme contains its cofactor.
77
What is a coenzyme?
A coenzyme is an organic cofactor for an enzymatic reaction (e.g., vitamin)
78
What is a prosthetic group?
A tightly bound cofactor is also known as a prosthetic group.
79
T/F, most coenzymes are synthesized by the body?
False, most coenzymes are obtained from outside sources.
80
What happens to the free energy (∆G) or a reaction if it is catalyzed by an enzyme?
The free energy of an enzyme-catalyzed reaction is the same as the reaction without the enzyme.
81
What happens as the concentration of substrate is increased in an enzyme-catalyzed reaction?
The reaction rate increases until most of the active sites are filled and then the reaction rate reaches a plateau.
82
T/F, at very high concentrations of substrate, reaction rate approximates Vmax?
True.
83
T/F, all enzymes in the body are proteins?
False, ribozymes are RNA enzymes.
84
What is the optimal pH for the enzymes of glycolysis?
7
85
What is the optimial temperature for most enzyme in the body?
37ºC
86
T/F, all enzymes in the body operate most efficiently at a pH of around 7.2?
False, enzymes in the digestive tract work best at acidic and basic pH's.
87
What is an allosteric enzyme?
An allosteric enzyme is an enzyme with two or more active sites. An allosteric enzyme oscillates between an active an inactive configuration.
88
What happens to an enzyme in the presence of an allosteric inhibitor?
An allosteric inhibitor prevents an enzyme from binding to its substrate by stabilizing the inactive configuration.
89
What are the three categories of enzymatic regulatory inhibition?
Feedback, reversible, and irreversible inhibition.
90
How does feedback inhibition regulate an enzymatic proces?
Feedback inhibition uses an end product as an allosteric inhibitor to the enzyme catalyzing the reaction.
91
What re the two types of reversible inhibitors?
The two types of reversible inhibitors are competitive and non-competitive inhibitors.
92
T/F, a noncompetitive inhibitor can be overcome by increasing the concentration of substrate?
False, a non-competitive inhibitor doesn't bind at the active site and therefore doesn't compete with the substrate.
93
T/F, a competitive inhibitor binds at the active site and therefore can be overcome by increasing the concentration of substrate?
True, a competitive inhibitor competes with the substrate for active sites.
94
How can a non-competitive inhibitor's effect be reversed?
Through the addition of compound having a greater affinity for the inhibitor than the inhibitor has for the enzyme.
95
T/F, Irreversible inhibition involves permanent damage to the active site?
True.
96
What is a zymogen?
A zymogen is an inactive form of an enzyme.
97
How is a zymogen activated? Give some examples of zymogens.
A zymogen is activated when a part of it is cleaved off. A few examples are digestive enzymes such as pepsinogen and chymotrypsinogen. (Note the "ogen" suffix.)
98
What is an anobolic process?
An anabolic process is a reaction that builds complex molecules and requires energy.
99
What is a catabolic process?
A catabolic process is a reaction that breaks down complex molecules and releases energy.
100
What is an autotroph?
An autotroph is an organism that can harness sunlight to create energy via photosynthesis (e.g., plants)
101
What is a heterotroph?
A heterotroph is an organism that breaks down organic nutrients for energy.
102
What are the energy carrier molecules for a cell's metabolic proceses?
ATP, NAD+, NADP+, and FAD
103
How to ATP, NAD+, NADP+, and FAD store energy?
ATP stores energy in its high-energy phosphate bonds. NAD+, NADP+, and FAD store energy in high-potential electrons.
104
Does oxidation result in the loss or gain of electrons?
Oxidation refers to the loss of electrons.
105
What happens to the number of electrons when a reactant gets reduced?
Reduction results in the gain of electrons.
106
T/F, an oxidizing agent gets oxidized during a reaction?
False, an oxidizing agent gets reduced and thereby causes another molecule to be oxidized.
107
What is the net reaction for glycolysis?
Glucose + 2ADP + 2Pi + 2(NAD+) ––––> 2Pyruvate + 2ATP + 2NADH + 2(H+) + 2H20
108
T/F, glycolysis results in substrate level phosphorylation of ADP?
True.
109
Is glycolysis an aerobic or anaerobic process?
Glycolysis is an anaerobic process.
110
What are the possible products of fermentation?
The products of fermentation are either ethanol or lactic acid.
111
When does a cell rely on fermentation of its energy needs?
A cell utilizes fermentation in an anaerobic (oxygen deficient) environment.
112
What is the net gain in ATP from cellular respiration?
Eukaryotes = 36 ATP; Prokaryotes = 38 ATP.
113
T/F, cellular respiration requires aerobic conditions?
True.
114
What are the three stages of cellular respiration?
The three stages of cellular respiration are: pyruvate decarboxylation, the citric acid (Krebs) cycle, and the electron transport chain.
115
T/F, During pyruvate decarboxylation, a molecule of CO2 is lost, leaving acetyl CoA?
True.
116
One molecule of glucose requies how many turns of the citric acid cycle?
The citric acid cycle (TCA) completes two cycles (turns) per molecule of glucose.
117
How many ATP, NADH, and FADH2 are created in one turn of the citric acid cycle?
Each turn of the citric acid cycle results in 1 GTP, 3 NADH, and 1 FADH2.
118
What is a cytochrome?
A cytochrome is a molecular electron carrier involved in oxidative phosphorylation.
119
When and where does oxidative phosphorylation occur?
Oxidative phosphorylation occurs at the inner mitochondrial membrane during the electron transport stage of cellular respiration.
120
Does the electron transport chain require oxygen?
Yes, the final acceptor of the electrons is O2, which then forms water.
121
T/F, the electron transport chain generates a proton gradient across the innter mitochondrial membrane?
True.
122
Where does glycolysis occur?
Glycolysis occurs in the cytoplasm.
123
Where does the citric acid cycle occur?
The citric acid cycle occurs in the inner mitochondrial matrix.
124
T/F, if glucose is unavailable, the body can use carbohydrates, fats and proteins to create energy?
True, Gluconeugenesis
125
What are the four stages of the cell cycle?
The four stages of the cell cycle are: G1, S, G2 and M.
126
When do a cell's chromosomes replicate?
The chromosomes replicate during the S (synthesis) stage of interphase.
127
What is the order of the four stages of mitosis?
Prophase, Metaphase, Anaphase, Telophase.
128
What is a chromatid?
A chromatid is one half of a replicated chromosome. Sister chromatids are attached by the centromere.
129
In which mitotic phase does spindle formation occur?
Spindle formation occurs during prophase.
130
In which mitotic phase are the chromosomes lined up in the equatorial plane?
The chromosomes line up during metaphase.
131
In which mitotic phase do the chromosomes separate?
The chromosomes separate during anaphase.
132
In which phase does cytokinesis occur?
Cytokinesis occurs during telophase.
133
How many chromosomes are in a human diploid cell?
A human diploid cell has 46 chromosomes.
134
How many chromosomes are in a human haploid cell?
A human haploid cell has 23 chromosomes.
135
What is a gametocyte?
A gametocyte is a haploid cell that undergoes meiosis.
136
T/F, homologous chromosomes code for different traits.
False, homologous chromosomes code for the same traits.
137
In what phase of meiosis would one fine a tetrad?
Tetrads exist in Prophase 1.
138
T/F, synapsis and crossing over result in genetic recombination?
True.
139
Name the different structures of the male reproductive tract.
SEVEN UP: Seminiferous tubules (testes), epididymis, vas deferens, ejaculatory duct, (nothing), urethra, penis.
140
What is the sequence of development for a mature sperm cell?
Primary spermatocyte, secondary spermatocyte, spermatid, and spermatoza.
141
What is an acrosome?
An acrosome is the enzyme-containing cap-like structure on the head of a sperm.
142
T/F, at birth, a female child's ova are arrested at prophase 1 and are called primary oocytes?
True.
143
Starting with the ovary, name the different structures of the female reproductive tract.
Ovary, oviduct (fallopian tube), uterus, cervix, vagina.
144
What are the corona radiata and zona pellucida?
The corona radiata is the outer layer of cells that surrounds the ovum. The zona pellucida is the inner layer of cells that surrounds the ovum.
145
What is a polar body?
A polar body is a small cell that results from unequal distribution of cytoplasm during meiosis.
146
T/F, dizygotic (fraternal) twins are identical?
False, monozygotic twins are identical.
147
Order the follwing embyonic stages: blastula, neurula, morula, gastrula, zygote.
zygote, morula, blastula, gastrula, neurula.
148
What is differentiation?
Differentiation is the specialization of cells that occurs during development.
149
What are the 3 primary germ layers?
Ectoderm, endoderm, and mesoderm.
150
What is induction?
Induction is the influence of a group of cells upon the differentiation of another group of cells.
151
When does the inner cell mass first appear?
Blastula.
152
When does the Archenteron first appear in development?
Gastrula.
153
When does the Notochord first appear in development?
Neurula.
154
When does the Trophoblast first appear in development?
Blastula.
155
When does the Blastopore first appear in development?
Gastrula.
156
When does the Neural fold first appear in development?
Neurula.
157
What structures arise from ectoderm?
Ectoderm - integument, lens of the eye, and nervous system.
158
What structures arise from endoderm?
Endoderm - epithelial linings of digestive and respiratory tracts, parts of liver, pancreas, thyroid, and bladder.
159
What structures arise from Mesoderm?
Mesoderm - musculoskeletal system, circulatory system, connective tissue, excretory system, and gonads.
160
T/F, the placenta and umbilical cord are responsible for fetal respiration, nutrition, and waste removal.
True.
161
T/F, adult hemoglobin has higher affinity for oxygen than fetal hemoglobin?
False, fetal hemoglobin has a higher affinity for oxygen.
162
What is the function of the ductus venosus?
The ductus venosis shunts blood away from the fetal liver.
163
What is the function of the foramen ovale?
The foramen ovale diverts blood away from the pulmonary arteries and into the left atrium.
164
What is the function of the ductus arteriosus?
The ductus arteriosus shunts blood directly from the pulmonary artery into the aorta.
165
In what trimester does the fetal heart begin to beat?
The heart begins to beat in the first trimester.
166
In what trimester do the skeleton and organs form?
The skeleton and organs are formed during the first trimester.
167
T/F, the allantois and yolk sac form the basis of the umbilical cord?
True.
168
From what structure does the placenta originate?
The placenta originates from the chorion.
169
What are the functions of the skeleton?
The functions of the skeleton are physical support, protection of delicate organs (e.g., brain), source of blood cells (i.e., bone marrow).
170
What are the two major componenets of the skeleton?
The major components of the skeleton are cartilage and bone.
171
Which type of cells secrete cartilaginous tissue?
Chondrocytes secrete cartilaginous tissue.
172
What are the two types of bone?
The two types of bone are compact bone and spongy bone.
173
What is periosteum?
The periosteum is the fibrous sheath of a bone.
174
What is the function of an osteoclast?
Osteoclasts are involved in bone reabsorption.
175
What is the function of an osteoblast?
Osteoblasts are involved in bone formation.
176
T/F, endochondral ossification is the replacement of cartilage with bone?
True.
177
What is intramembranous ossification?
Intromembranous ossification is the transformation of mesenchymal tissue into bone.
178
What is the function of a ligament?
Ligaments connect bone to bone and strengthen joints.
179
What is synovial fluid?
Synovial fluid is a lubricant found in movable joints.
180
What are the three distinct types of muscle in mammals?
The three types of muscle are skeletal, cardiac, and smooth.
181
What is the sarcoplasmic reticulum?
The sarcoplasmic reticulum is a modified endoplasmic reticulum that stores calcium ions (in a muscle cell).
182
T/F, within a sarcomere, thick filaments are made of actin and thin filaments are made of myosin?
False, thin filaments are made of actin and thick filaments are made of myosin.
183
During contraction, what happens to the width of the A-band?
The A band is always of constant width.
184
During contraction, what happens to the H zone and I band?
The H zone and the I band contract and decrease in length.
185
T/F, the release of Ca^2+ by the sarcoplasmic reticulum initiates muslce contraction?
True.
186
T/F, the sarcoplasmic reticulum must uptake Ca^2+ for relaxation to occur?
True.
187
T/F, a muscle fiber exhibits an "all-or-nothing" response?
True.
188
Which components of the nevous system innerviates smooth muscle?
Smooth muscle is innervated by the autonomic nervous system.
189
Which types of muscle are striated?
Cardiac and skeletal muscle are striated.
190
Which types of muscle display myogenic activity?
Cardiac and smooth muscle display myogenic activity.
191
What is the role of calcium in the initiation of sarcomere contraction?
Calcium binds with troponin, which causes a conformational shift in tropomyosin, expressing the myosin binding site.
192
Which compound is needed to release myosin from its binding site on actin?
ATP is needed to release myosin from its binding site on actin.
193
Name the structures of the human alimentary canal (in order).
Oral cavity, pharynx, esophagus, stomach, small intestine, large intestine.
194
What enzyme does saliva containand what does it digest?
Saliva contains salivary amylase, which digests starch (carbohydrates).
195
T/F, chief cells secrete HCL into the stomach?
False, chief cells secrete pepsinogen into the stomach; parietal cells secretes HCL into the stomach.
196
What is the peristalisis?
Peristalsis is defined as the wave-like smooth muscle contractions that propel food through the digestive tract.
197
What do parietal cells secrete into the stomach?
Parietal cells secrete HCL into the stomach.
198
What two sphincters separate the stomach from the rest of the alimentary canal?
The cardiac sphincter and the pyloric sphincter.
199
What are the three segments of the small intestine?
The small intestine is divided into the duodenum, jejunum, and ileum.
200
Which segment(s) of the small intestine is/are primarlily responsible for digestion?
The duodenum is primarily responsible for digestion.
201
Which segment(s) of the small intestine is/ are primarily responsible for abosrption?
The jejunum and ileum are primarily responsible for absorption.
202
Why is pancreatic juice basic (high pH)?
Pancreatic juice contains bicarbonate ion, which serves to neutralize the acidic chyme from the stomach. This is necessary because pancreatic enzymes work best at a slightly basic pH.
203
T/F, bile is manufactured in the liver, stored in the gall baldder, and facilitates lipid digestion?
True.
204
What are the three components of the large intestine?
The large intestine is derived into the cecum, colon, and rectum.
205
What is the primary function of the large intestine?
The large intestine functions primarily to absorb water and salts.
206
Where do protein digestion and lipid digestion begin?
Protein digestion begins in the stomach and lipid digestion begins in the small intestine.
207
Which component of the nervous system inhibits digestion? Which component promotes digestion?
The sympathetic nervous system inhibits digestion. The parasympathetic nervous system stimulates digestion.
208
What is the fuctional site and nutrient Chymotrypsin digests?
Small intestine and digests protein.
209
What is the fuctional site and nutrient Pepsin digests?
Stomach and digests Proteins.
210
What is the fuctional site and nutrient Lipase digests?
Small intestine and digests lipids.
211
What is the fuctional site and nutrient Sucrase digests?
Small intestine and digests Starch.
212
What is the fuctional site and nutrient Trypsin digests?
Small intestine and digests Protein.
213
What is the fuctional site and nutrient Carboxypeptidase digests?
Small intestine and digests Protein.
214
What is the fuctional site and nutrient Maltase digests?
Small intestine and digests Starch.
215
What is the fuctional site and nutrient Salivary amylase digests?
Mouth and digests starch.
216
Correctly sequence the following strcutures of the respiratory tract:
Alveoli, trachea, larynx, nares, pharynx, bronchi, bronchioles.
Nares, pharynx, larynx, trachea, bronchi, bronchioles, alveoli.
217
What is the function of sarfactant?
Surfactant reduces surface tension on alveoli and facilitates gas exchange.
218
T/F, the diaphragm contracts during exhalation?
False, the diaphragm relaxes during exhalation and contracts during inhalation.
219
Which part of the brain controls breathing?
The medulla oblongata controls breathing.
220
Define vital capacity.
Vital capacity is the maximum amount of air that can be inhaled.
221
Define tidal volume.
Tidal volume is the normal amount of air inhaled.
222
Define residual volume.
Residual volume is air that always remains in the lungs.
223
T/F, total lung capacity = tidal volume + residual volume?
False, total lung capacity = vital capacity + residual volume.
224
What happens to respiratory rate when high concentrations of CO2 and / or H+ are in the blood?
Respiratory rate increases.
225
T/F, blood entering the pulmonary capillaries has a higher partial pressure of O2 than the air in the alveoli?
False, O2 partial pressure is lower in the pulmonary capillary blood than in the alveolar air.
226
How does the partial pressure of CO2 in a capillary compare with the partial pressure of CO2 in alveolar air?
The partial pressure of CO2 in the capillaries is higher than in the the alveolar air.
227
T/F, all arteries carry oxygenated blood and all veins carry deoxygenated blood?
False, pulmonary arteries and umbilical arteries carry deoxygenated blood while pulmonary veins and umbilical veins carry oxygenated blood.
228
T/F, the right side of the heart pumps blood into pulmonary circulation and the left side pumps blood into systemic circulation?
True.
229
Starting with the right atrium, trace the path of blood flow throughout the body?
Right atrium, right ventricle, pulmonary arteries, pulmonary capillaries, pulmonary veins, left atrium, left ventricle, aorta, arteries, arterioles, capillaries, venules, veins, vena cava.
230
Which valve separates the right atrium and right ventricle?
The tricuspid valve separates the right atrium from the right ventricle.
231
Which valvel separates the left atrium and left ventricle?
The mitral valve separates the left atrium from the left ventricle.
232
T/F, systole is when the heart relaxes and diastole is when the venticles contract?
False, the ventricles contract during systole and the heart relaxes during diastole.
233
What is the electrical pathway in the heart?
Electrical conduction pathway: sinoatrial node -> atrioventricular node -> bundle of His ->Purkinje fibers.
234
Which nerve of the parasympathetic nervous system decreases heart rate?
The vagus nerve.
235
Which component of the nervous system increases heart rate?
Sympathetic nervous system stimulation causes an increase in heart rate.
236
Which component of the nervous system increases heart rate?
Sympathetic nervous system stimulation causes an increase in heart rate.
237
What is plasma?
Plasma is the liquid component of blood.
238
What are the cellular components of blood?
The cellular components of blood are erythrocytes, leukocytes and platelets.
239
T/F, the three types of leukocytes are granular leukocytes, lymphocytes, and monocytes.
True
240
Which type of leukocyte plays a key rols in inflammation and allergic reactions?
Granular leukocytes (basophils, eosinophils, and neutrophils) are active in inflammation and allergic reactions.
241
Which type of leukocyte plays a key role in immune response?
Lymphocytes are key players in immune response.
242
What is the function of a monocyte?
A monocyte phagocytizes foreign matter.
243
What are the four blood types?
The four blood types are A, B, AB and O.
244
Which blood type is considered to be a universal donor? Which type is a universal recipient?
Type O blood is considered to be a universal donor. Type AB blood is considered to be a universal recipient.
245
What is the Rh factor? How can the Rh factor compliate pregnancy?
The Rh factor is an antigen on the surface of RBCs. Following the birth of an Rh+ child, and Rh- mother develops antibodies to the Rh factor. These antibodies can attack the blood cells of any future Rh+ fetuses carried by the mother.
246
Accordign to the Bohr effect, would high levels of H+ and HCO3- increase or decrease hemoglobin's affinity for O2?
High levels of H+ and HCO3 would decrease hemoglobin's affinity for O2.
247
T/F, platelets play a key role in the immune response?
False, platelets are key players in clot formation.
248
Which proteins are essential for proper clotting?
Thrombin and fibrin are essential for clot formation.
249
T/F, B lymphocytes are involved in humoral immunity?
True.
250
What is the function of immunoglobins (antibodies)?
Antibodies attract other cells that can phagocytize an antigen or cause the antigens to clump together.
251
What role do T lymphocytes play in an immune response?
T lymphocytes are involved in cell-mediated immunity. They are responsible for the body's defense against viral and fungal infections.
252
T/F, skin ciliated muose, macrophages, and inflammatory responses are all examples of nonspecific defense mechanisms?
True.
253
What happens to interstitial fluid that doesn't diffuse into a capillary?
Excess interstitial fluid is picked up by the lymphatic system and returned to the circulatory system.
254
What is a lymph node and what is its function?
A lymph node is swelling along a lymphatic vessel that contains phagocytic cells. Their role is to filter the lymph and remove/ destroy foreign particles.
255
Define homeostasis.
The maintenance of a stable internal environment.
256
What are the primary homeostatic organs in mammals?
The primary homeostatic organs are the kidneys, liver, large intestine, and skin.
257
What are the three regions of a kidney?
The three regions of a kidney are the pelvis, medulla, and cortex.
258
T/F, a nephron is situated such that the loop of Henle runs through the medulla?
True.
259
What is the primary purpose of the kidney?
The primary purpose of the kidneys is to regulate salt and water concentration in the blood.
260
Where are the amino acids, glucose, and vitamins reabsorbed in the nephron?
Amino acids, glucose, and vitamins are reabsorbed into proximal convoluted tubule.
261
Where in the loop of Henle does water passively diffust out?
Water passively diffuses out of the descending limb.
262
T/F, water passively diffuses into the ascending limb?
False, the ascending limb is impermeable to water.
263
T/F, aldosterone stimulates the reabsorption of Na+ and H2O from the distan tubule and collectuing duct?
True.
264
Would high levels of aldosterone result in concentrated or diluted urine?
High levels of aldosterone result in concentrated urine.
265
How would low levels of aldosterone affect blood pressure?
Low levels of aldosterone lead to reduced blood plasma volume and therefore reduced blood pressure.
266
Would high levels of ADH (vasopressin) result in the concentrated or dilute urine?
High levels of ADH result in the concentrated urine.
267
Where and how does ADH affect the nephron?
ADH makes the distal convoluted tubule and collecting duct more permeable to H2O.
268
T/F, urine leaves the kindey via the ureter and leaves the bladder via the urethra?
True.
269
Is urine hypertonic or hypotonic to blood?
Urine is hypertonic to blood.
270
What are some of the functions of the liver?
Liver functions include regulation of blood glucose, detoxification of toxins, beta-oxidation of fatty acids, and destruction of old red blood cells.
271
T/F, the large intestine functions as an excretory organ by getting rid of excess salts?
True.
272
In which layer of the skin are seat glands, sense organs, and blood vessels located?
Sweat glands, sense organs and blood vessels are located in the dermis.
273
T/F, constriction of blood vessels in the skine leads to decreased body temperature?
False, constriction of blood vessels in the skin leads to increased body temperature.
274
What is the difference between an endocrine gland and an exocrine gland?
Endocrine glands secrete their hormones directly into the blood stream. Exocrine glands secrete substances that are transported by ducts.
275
What is the difference between a tropic hormone and a direct hormone?
Tropic hormones stimulate other endocrine glands, while direct hormones act directly on the target organ.
276
The anterior pituitary is regulated in part by what other endocrine gald?
The hypothalamus regulates the anterior pituitary.
277
Name all of the hormones secreted by the anterior pituitary gland?
The anterior pituitary secretes growth hormone (GH), prolactin, adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH), endorphins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH).
278
T/F, growth hormone promotes bone and muscle growth?
True.
279
What is the function of prolactin?
Prolactin stimulates the production of breast milk.
280
What is the target gland of ACTH?
ACTH acts on the adrenal cortex.
281
What is the function of TSH?
TSH causes the thyroid to uptake iodine and produce thyroid hormone.
282
T/F, LH and FSH are secreted only in females?
False, LH and FSH are produced and secreted in males as well as females.
283
Name the hormones synthesized by the posterior pituitary?
None, the posterior pituitary stores hormones (oxytocin and ADH) that are synthesized in the hypothalamus.
284
What two hormones are released by the posterior pituitary and what are their functions?
Oxytocin increases the strength of contractions during childbirth. Antidiuretic hormone (ADH, vasopressin) promotes the absorption of water in the nephron.
285
T/F, the hypothalamus regulates both the anterior and the posterior pituitary through hormone secretion and neurosecretory cells?
True.
286
Name the hormones scecreted by the thyroid gland?
The thyroid gland secretes thyroxine and triiodothyronine (collectively known as thyroid hormones), as well as calcitonin.
287
How do the thyroid hormones affect metabolism?
Thyroid hormones increase metabolism.
288
How does calcitonin affect the level of Ca2+ in blood plasma?
Calcitonin decreases blood plasma Ca2+.
289
What hormone does the parathyriod gland produce and what is its function?
The parathyroid secretes parathyriod hormone, which serves to increase blood plasma Ca2+
290
Name the three types of hormones secreted by the adrenal cortex.
The three types of hormones are glucocorticoids, mineralocorticoids, and cortical sex hormones.
291
What is the function of cortisol?
Cortisol is a glucocorticoid that increases the blood's glucose level.
292
What important mineracorticdoid is released by the adrenal cortex?
Aldosterone is an important mineralocorticoid released by the adrenal cortex.
293
Which endocrine gland secretes epinephrine and noepiniphrine?
The adrenal medulla secretes epinephrine and norepinephrine.
294
T/F, epinephrine and norepinephrine return the body to its restin state and increase nutrient absorption.
False, they slow down digestion and increase the basal metabolic rate.
295
What are some of the effects of epinephrine?
```
Epinephrine effects include:
Increased heart rate.
Increased blood glucose level.
Increased blood supply to brain, muscle, and heart.
Decreased digestion and excretion.
```
296
Which endocrine organ secretes insulin and glucagon?
The pancreas secretes insulin and glucagon.
297
How does glucagon affect bood glucose levels?
Glucagon increases blood glucose levels.
298
How does insulin affect blood glucose levels?
Insulin decreases blood glucose levels.
299
T/F, too much insulin causes hypoglycemia?
True.
300
What is the function of somatostatin?
Somatostatin inhibits both glucagon and insulin secretion.
301
T/F, the testes secrete testosterone?
True.
302
Which is two hormones are secreted by the ovaries?
The ovaries secrete estrogen and progesterone.
303
What are the four phases of the menstrual cycle?
The four phases of the menstrual cycle are follicular phase, ovulation, luteal phase, and menstruation.
304
What is the corpus luteum?
The corpus luteum develops from a ruptured follicle in the ovary and secretes estrogen and progesterone.
305
T/F, the pineal gland secretes melatonin?
True.
306
How do peptide hormones act on their target cells?
Peptide hormones bind to receptors on the cell membrane, thereby initiating a chain of reactions inside the cell (secondary messengers.)
307
How do steroid hormones act on their target cells?
Steroid hormones pass through the cell membrane and act directly inside the cell.
308
T/F, amino-acid-derived hormones act on their target cells directly?
False, some amino-acid-derived hormones act on their target cells directly, while others behave as peptide hormones and use messengers.
309
What is the function of a dendrite?
A dendrite conducts nerve impulses towards the cell body.
310
What is the function of an axon?
An axon conducts nerve impulses away from the cell body.
311
What is the composition of a myelin sheath?
In the CNS, myelin is composed of the membranes of oligodendrocytes. In the PNS, myelin is composed of the membranes of Schwann cells.
312
What protein complex is responsible for the resting potential (-70 mV) of a neuron?
The Na+ / K+ pump is responsible for the neuron's resting potential.
313
T/F, in a resting neuron, Na+ concentrations is higher inside the cell than outside the cell?
False, Na+ concentration is higher outside a resting neuron.
314
Do Na+ ions rush into or out of the cell during depolarization?
Na+ ions rush into a cell during depolarization.
315
Do Na+ ions rush into or out of the cell during repolarization?
During repolarization, K+ ions rush out of the cell.
316
T/F, a neuron can conduct during the refractory period?
False, the neuron is unable to respond to stimulus during the refractory period.
317
What is hyperpolarization?
Hyperpolarization refers to a state where the potential across the membrane is more negative than the resting potential.
318
What is saltatory conduction?
Saltatory conduction is the "jumping" of an action potential between the unmyelinated Nodes of Ranvier.
319
What happens when an action potential reaches a synapse (in a mammal)?
When an action potential reaches a synapse, the electrical signal causes the release of neurotransmitters from the presynaptic membrane into the synapse.
320
What is the function of a sensory (afferent) neruon?
A sensory neuron carries impulses from sensory organs to the brain and spinal cord.
321
What is the function of a motor (efferent) neuron?
A motor neuron transmits impulses from the brain and spinal cord to muscles or glands.
322
Which type of neuron serves as a link between motor and sensory neurons?
Interneurons (associate neurons) link sensory and motor neurons.
323
What are the two major subsystems of the nervous system?
The two major subsystems of the nervous system are the central nervous system and the peripheral nervous system.
324
What are the components of the central nervous system?
The central nervous system comprises the brain and spinal cord.
325
T/F, gray matter is composed of axons and white matter is composed of cell bodies?
False, gray matter is composed of cell bodies and white matter is composed of axons.
326
What is the largetst part of the human brain?
The cerebral cortex is the largest part of the human brain.
327
What is the function of the cerebral cortex?
The cerebral cortex processes and integrates sensory input and motor response, and controls memory.
328
what is the function of the hypothalamus?
The hypothalamus is responsible for visceral functions such as hunger, thirst, and sex drive.
329
T/F, the cerebral cortex is the relay center for the visual and auditory impulses?
False, the midbrain is the relay center for visual and auditory impulses.
330
What are the components of the hindbrain?
The hindbrain is composed of the cerebellum, pons, and medulla oblongata.
331
What is the function of the cerebellum?
The cerebellum is responsible for coordination.
332
What part of the brain controls autonomic activities?
The medulla oblongata controls autonomic activities.
333
What are the four regions of the spinal cord?
The four regions of the spinal cord are cervical, thoracic, lumbar, and sacral.
334
T/F, dorsal root ganglia house the cell bodies of snsory root fibers?
True.
335
T/F, sensory nerves enter the spinal cord ventrally and motor nerves leave the spinal cord dorsally?
False, sensory nerves center dorsally and motor nerves leave ventrally.
336
Illustrate the hierarchy of the divisions of the peripheral nervous system?
PNS: Sensory and Motor
Motor: Somatic and Automatic
Automatic: Parasympathetic and Sympathetic
337
What is the difference between polysynaptic and monosynaptic reflex?
A monosynaptic reflex involves only one sensory neuron and one motor neuron. A polysynaptic reflex involves one or more interneurons, in addition to a sensory neuron and a motor neuron.
338
Which part of the nervous system readies the body for "fight or flight"?
The sympathetic nervous system readies the body for "fight or flight"
339
What is the function of the parasympathetic division of the nervous system?
The parasympathetic division opposes the sympathetic division by slowing the body down and conserving energy.
340
Which division of the nervous system inhibits digestion?
The sympathetic division inhibits digestion.
341
Which type of photoreceptor cell is specialized for color vision? Which type is specialied for low light conditions?
Cones are for color and rods are for night vision.
342
What is the fovea?
The fovea is the region of the retina with a high density of cones.
343
What are the components of the middle ear?
The middle ear is composed of the tympanic membrane, malleus, incus, and stapes.
344
What are the components fo the innear ear?
The inner ear is composed of the cohlea (which contains the organ of Corti) and the semicircular canals.
345
What are alleles?
Alleles are different forms of the same gene. Alleles occupy the same position on homologous chromosomes.
346
Define genotype.
Genotype refers to the genetic makeup of an individual.
347
Define phenotype.
Phenotype refers to the physical manifestation of an individual's genotype.
348
Define homozygous.
Homozygous individuals have two copies of the same allele for a given trait.
349
Define heterzygous.
Heterozygous individuals have two different alleles for a given trait.
350
Summarize Mendel's First Law (Law of Segregation)
Mendel's first law states that alleles segregate during meiosis; specifically:
–Genes exist in alternative forms (alleles).
–An individual inherits two alleles for each train, one from each parent.
–The two alleles segregate during meiosis.
–If two different alleles are present, only one will be fully expressed.
351
Summarize Mendel's Second Law (Law of Independent Assortment).
Mendel's second law states that alleles of unlinked genes assort independently during meiosis.
352
Given: P = dominant (purple) and p = recessive (white)
| What would be the phenotypic ration of a PP x pp cross?
PP x pp = 100% purple
353
Given: P = dominant (purple) and p = recessive (white)
| What would be the phenotypic ratio of a Pp x Pp cross?
Pp x Pp = 75% purple: 25% white
354
Given: P = dominant (purple) and p = recessive (white)
| What would be the phenotypic ratio of a Pp x pp cross?
Pp x pp = 50% purple: 50% white.
355
Given: P = dominant (purple) and p = recessive (white)
| What would be the genotypic ration of a Pp x pp cross?
Pp x pp = 50% Pp "purple" : 50% pp "white"
356
Given: P = dominant (purple) and p = recessive (white)
| What would be the genotypic ration of a Pp x Pp cross?
Pp x Pp = 25% PP : 50% Pp : 25% pp
=75% purple (PP and Pp)
=25% white (pp)
357
T/F, recombinant frequencies are roughly additive.
True.
358
Given: X and Y recombinant frequency = 5%
X and Z recombinant frequency = 13%
What is the Y and Z recombinant frequency if the gene order is XYZ?
8%
359
Given: X and Y recombinant frequency = 5%
X and Z recombinant frequency = 13%
What is the Y and Z recombinant frequency if the gene order is YXZ?
18%
360
What is a map unit?
1 map unit = 1% recombinant frequency.
361
Red flowers crossed with white flowers yield pink flowers. What kind of dominance is portrayed in this example?
Incomplete dominance.
362
Assuming codominance, what happens to the phenotype in the presence of two dominant alleles?
The phenotype of each allele is simultaneously displayed. (e.g., type AB blood).
363
What is penetrance of a genotype?
The penetrance of a genotype is the percentage of individuals in a population who actually express its phenotype.
364
What is expressivity of a genotype?
The expressivity of a genotype is the degree to which the phenotype is expressed in an individual.
365
T/F, in humans, most sex-linked genes are located on the Y chromosome?
False, most sex-linked genes are on the X chromosome.
366
What percentage of daugters will inherit their father's sex-linked gene?
100% of daughters will inherit their father's sex-linked gene.
367
What percentage of sons will inherit their father's sex linked gene?
0% of sons will inherit their father's sex-linked gene.
368
What percentage of sons will inherit their mother's sex-linked gene (assumuing a heterozygous mother)?
50% of sons will inherit their mother's sex-linked gene.
369
T/F, Females can express a sex-linked recessive trait?
True, a female carrier and a male with the recessive trait will have a 25% chance of giving birth to a female chile with the recessive trait.
370
What is nondisjunction?
Nondisjunction is the failure of homologous chromosomes (or sister chromatids) to separate properly during cellular reproduction.
371
What are the three different results of chromosomal breakage?
Duplication–The fragment joints with its homologous chromosome.
Translocation–The fragment joins with a non-homologous chromosome.
Inversion–The fragment rejoins its original chromosome but in the reverse position.
372
Name the four nitrogenous bases in DNA.
Adenine, cytosine, guanine, thymine.
373
Name the purines and pyrimidines.
The purines are adenine and guanine. The pyrimidines are cytosine, thymine, and uracil.
374
What is the base-pairing in DNA? How many bonds hold the bases together?
Adenine - Thymine (2 hydrogen bonds)
| Cytosine - Guanine (3 hydrogen bonds)
375
Name three differences between RNA and DNA.
RNA uses ribose instead of deoxyribose.
RNA replaces thymine with uracil.
RNA is usually single-stranded.
376
T/F, DNA synthesis proceeds in the 3' to 5' direction.
False, DNA synthesis proceeds in the 5' to 3' direction.
377
What are the four types of RNA, and what are their functions?
```
Messenger RNA (mRNA) - contains the codons for peptide chain synthesis.
Transfer RNA (tRNA) - transports amino acids to the ribosome during protein synthesis.
Ribosomal RNA (rRNA) - structural component of ribosomes.
```
Heterogeneous nuclear RNA (hnRNA) - precursor of mRNA.
378
What is transcription?
Transcription is the process whereby mRNA is synthesized from a DNA template.
379
What is translation?
Translation is the process whereby proteins are synthesized from a mRNA template.
380
What is an exon? An intron?
An exon is a coding sequence on a gene. An intron is a non-coding sequence on a gene.
381
What is a codon?
A codon is a 3-base sequence on mRNA that codes for a specific amino acid.
382
What is an anticodon?
An anticodon is a 3-base sequence on tRNA that is complementary to a mRNA codon.
383
What are the three stages of polypeptide synthesis?
The three stages of polypeptide synthesis are initiation, elongation, and termination.
384
What are the three types of base pair mutations that can occur duruing protein synthesis?
Types of base-pair mutations are substitutions, insertions, and deletions.
385
T/F, a frameshift mutation usually leads to a non-functioning protein?
True.
386
What types of nucleic acid can ben found in a virus?
A virus can contain DNA or RNA.
387
What is a retrovirus?
A retrovirus is an RNA virus that codes for the enzyme reverse transcriptase, which uses the RNA as a template for DNA synthesis.
388
What is a prophage (provirus)?
A prophage is a virus that has integrated its DNA into the host cell's DNA.
389
What is a bacteriophage?
A bacteriophage is a virus that attacks only bacteria.
390
Describe the lytic and lysogenic cycles.
Bacterphage infection results in either a lytic or a lysogenic cycle. A lytic cycle results in the production of new progeny that cause the cell to burst (lyse). A lysogenic cycle results in the incorporation of the viral DNA into the bacterial DNA where it remains inactive. A lysogenic cycle may progress to al lytic cycle.
391
What are the three mechganisms by which bacteria can increae genetic variability?
Transformation - incorporation of foreign chromosome fragments.
Conjugation - transfer of genetic material between two bacteria.
Transduction - virus carries DNA between two bacteria.
392
What is an operon?
An operon is a gene that regulates (bacterial) transcription.
393
What is an inducible system?
An inducible system requires the presence of an inducer for transcription to occur.
394
What is a repressible system?
A repressible system is in a constant state of transcription unless a corepressor is present to inhibit transcription.
395
Define fitness according to Darwin?
Fitness is the ability of an organism to mate and produce fertile offspring.
396
Describe the model of punctuated equilibruim.
The model of punctuated equilibrium holds that evolution is characterized by long periods of stasis punctuated by rapid evolutionary changes.
397
What are homologous sturctures?
Homologous structures are similar in structure and origin but no function (e.g., whale flippers / human arms).
398
What are analogous structures?
Analogous structures are similar in function but not in origin (e.g., insect wings / bird wings).
399
What are vestigial structures?
A vestigial structure is a remnant structure that has lost its ancestral function (e.g., tail bone in man).
400
Given the Hardy - Weinberg equation: p^2 + 2pq + q^2 = 1
| What does p^2 represent?
p^2 = frequency of homozygous dominants.
401
Given the Hardy - Weinberg equation: p^2 + 2pq + q^2 = 1
| What does 2pq represent?
2pq = frequency of heterozygotes.
402
What does q^2 represent?
q^2 = frequency of homozygous recessives.
403
T/F, p + q = 1?
True.
404
What are the 5 necessary conditions for the Hardy-Weinberg equation to hold true?
1. there are no mutations that affect the gene pool.
2. The population must be very large.
3. Genes in a population are equally successful at reproducing.
4. Mating occurs randomly.
5. There is no net migration of individuals into or out of the population.
405
How does genetic drivt differ from gene flow?
Genetic drift refers to changes in the gene pool due to chance. Gene flow refers to the changing of the gene pool due to the migration of individuals.
406
T/F, stabilizing selection maintains a well adapted uniform character in a population?
True.
407
How does a disrubptive selection affect the phenotype of a population?
Disruptive selection favors the phenotypical extremes, leading the the expression of two or more phenotypic forms.
408
How does directional selection affect the phenotype of a population?
Directional selection favors the expression of one phenotypical extreme.
409
When are two populations descending from the same ancestral stock considered to be different species?
Two populations are considered to be different species when they can no longer interbreed and produce viable offspring.
410
What is adaptive radiation?
Adaptive radiation is the emergence of a number of distinct lineages from a single ancestral species. The different lineages usually result when a group begins to exploit a different niche.
411
Describe convergent evolution.
Convergent evolution refers to the independent development of similar characteristics by non-related groups.
412
Describe parallel evolution.
Parallel evolution refers to the process whereby related groups independently develop similar characteristics due to analogous environmental pressures.
413
Describle divergient evolution.
Divergent evolution refers to the process whereby related groups independently develop dissimilar characteristics.
