Biology 20
Exam #2 Practice Questions
1. The cells of an ant and an elephant are, on average, the same small size; an elephant just has more of them.
What is the advantage of small cell size?
a) small cells are less likely to burst than large cell;
b) small cells are less likely to be infected by bacteria;
c) small cells can better take up what they need from their environment;
d) it takes less energy to make an organism out of small cells;
e) small cells can "morph" more easily than larger cells.
2. Which of the following supports the claim the mitochondria developed from bacteria that, long ago, were
incorporated into eukaryotic cells by the process of phagocytosis?
a) Mitochondria has flagella for motion;
b) mitochondria have proteins for synthesis of ATP
c) mitochondria are the “powerhouses” of the cell;
d) mitochondria are easily transported across membranes;
e) mitochondria have their own DNA.
3. Sodium ions (Na+) diffuse across the cell membrane, but they need assistance. This would be an example of:
a) simple diffusion; b) facilitated diffusion;
c) active transport;
d)osmosis;
e) huh?
4. You're rushed to the ER and given an IV (intravenous) saline (salt) solution to rehydrate you. The nurse was
sleeping during biology this time and happened to give you an hypotonic IV solution. What would happen to
your RBC's (red blood cells) in your blood vessels?
a) shrivel;
b) lyse/burst;
c) nothing;
d) you're thinking lawsuit aren't you?
5. [Ca++] is 2.5 mM outside the cell and 0.0001 mM inside the cell. Which direction will the Ca++ ions want to
flow?
a) into the cell
b) out of the cell;
c) no net movement into or out of the cell;
d) when did you talk about ion concentrations?
e) none of these are correct.
6. Which of the following relationships below is incorrect?
a) cell wall = support & protection; b) chromosomes = genetic control;
c) ribosomes = protein synthesis;
d) chloroplasts = chief site of cellular respiration;
e) mitochondria = ATP formation;
7.
Just the other day, I told you about a recent article where a man in Germany had leukemia and was HIV
positive. Doctors gave him a bone marrow transplant from and individual who had a genetic mutation where
HIV could not infect his T lymphocytes. As a result of the bone marrow transplant, this man is now in
remission from leukemia and his HIV levels are nonexistent. What was the reason his HIV levels are now
nearly in detectable? Did I talk about this with you guys???
a) the doctors transplanted antiviral drugs also;
b) after the transplant, he did not produce certain membrane proteins;
c) better T-lymphocytes were transplanted;
d) the bone marrow resulted in stronger white blood cells capable of fighting the virus;
e) it was miracle;
ab) the researchers lied about their findings
8. You decide to do an experiment with celery stalks and osmosis. You immerse celery stalks in freshwater for
several hours become stiff and hard. Similar stalks are left in ocean water become limp and soft. From this
you could deduce that the cells of the celery stalks are:
a) hypotonic to both freshwater and ocean water;
b) hypertonic to both freshwater and ocean water;
c) hypertonic to freshwater, but hypotonic to ocean water;
d) hypotonic to freshwater, but hypertonic to ocean water;
e) where’s that gin and tonic???
9.
Which of the following is present in prokaryotic cells?
a) ribosomes; b) mitochondria; c) nuclear envelope;
d) ER;
e) all of these are present.
10. A plant cell placed in distilled water (100%) will
where as an animal cell placed into distilled water
will
.
a) burst...burst;
b) become flaccid...shrivel;
c) become turgid...be normal shaped;
d) become turgid...burst;
e) I have not idea what you're talking about.
11. Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are
changing:
a) chemical energy into kinetic energy;
b) chemical energy into potential energy;
c) kinetic energy into potential energy;
d) kinetic energy into chemical energy.
12. Oxidation is the
, where as reduction is the
.
a) gain of electrons ... loss of electrons;
b) loss of electrons ... gain of electrons;
c) loss of oxygen ... gain of oxygen; d) gain of oxygen ... loss of oxygen.
13. When an enzyme catalyzes a reaction; it?
a) lowers the amount of energy that is required to get the reaction going;
b) raises the amount of energy that is required to get the reaction going;
c) becomes the product of the reaction;
d) acts as the reactant.
14. After you have broken down your breakfast items into simpler products. The chemical reactions that result in
the building of more complex molecules are referred to as
reactions.
a) anabolic; b) catabolic;
c) dehydration; d) none of these.
15. Three or four of the following statements concerning enzymes are true and c orrect. Which one, if any, is NOT
correct? If all the statements are correct, choose "All of the above are correct statements."
a) Enzymes are proteins;
b) An enzyme is not consumed by the catalytic process;
c) An enzyme is very specific in terms of whi
ch substrates it can bind to;
d) An enzyme lowers the activation energy of a chemical reaction
e) all of these are correct statements regarding enzymes.
16. Which of these statements about enzyme inhibitors is true?
a) A competitive inhibitor binds to the enzyme outside the active site;
b) the action of competitive inhibitors may be reversible or irreversible;
c) A noncompetitive inhibitor does not change the shape of the active site;
d) When the product of an enzyme or an enzyme sequence acts as its inhibitor, this is known as positive feedback;
e) Antibiotics and pesticides generally do not act on enzymes, but rather affect the genetic code of their victims.
17. A reaction is designated as exergonic rather than endergonic when ___________.
a) activation energy exceeds net energy release;
b) activation energy is necessary;
c) no kinetic energy is released;
d) the potential energy of the products is less than the potential energy of the reactants;
e) it absorbs more energy.
18. The first law of thermodynamics ____________.
a) states that energy is neither created not destroyed;
d) states that entropy spontaneously increases;
b) deals with entropy; c) deals with heat content;
e) predicts the direction of a reaction.
19. Which of these is exhibiting kineticenergy?
a) a rock on a mountain ledge;
b) the high energy phosphate bonds of ATP;
c) an archer with a flexed bow;
d) a space station orbiting Earth;
e) a person sitting on a couch while watching TV.
20. Which of the following do enzymes work on?
a) substrates;
b) products;
c) inhibitors;
d) competitive inhibitors; e) dynamite.
21. You’ve cut your finger and your body repairs it. What type of reaction just occurred?
a) endergonic and anabolic;
b) endergonic and catabolic;
c) exergonic and anabolic;
d) endergonic and catabolic;