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Name: ________________________________
Choose any 12
Short Answers:
. 4 pts. each.
1. Distinguish between prokaryotic and eukaryotic cells.
2. Define cohesion and adhesion.
3. Explain the advantages of compartmentalization in eukaryotic cells.
4. Describe the role of NAD+ in cellular respiration.
5. Describe the two major dynamic processes of any ecosystem.
Bio 101 - Midterm
6. Define the terms kinetic energy and potential energy. Explain why electrons in the first electron shell have
less potential energy than electrons in higher electron shells.
7. Explain how the primary structure of a protein is determined.
8. Distinguish among nonpolar covalent, polar covalent and ionic bonds.
9. List 4 major functions of membrane proteins.
10. Explain how ATP performs cellular work
11. Explain why a concentration gradient of a substance across a membrane represents potential energy.
12. Trace the general movement of electrons in noncyclic electron flow. Trace the general movement of electrons in
cyclic flow. Why are there 2 types of electron flow?
13. Explain in general terms how redox reactions are involved in energy exchanges.
Multiple Choice: 1 pt. each.
1. What is the approximate atomic mass of an atom with 16 neutrons, 15 protons and 15 electrons?
15 daltons
16 daltons
30 daltons
31 daltons
E) 46 daltons
2. A compound contains hydroxyl groups as its predominant functional group. Which of the following statements
is true concerning this compound?
A) It lacks an asymmetric carbon, and it is probably a fat or lipid.
B) It should dissolve in water.
C) It should dissolve in a nonpolar solvent.
D) It won't form hydrogen bonds with water.
E) It is hydrophobic.
3) The presence of cholesterol in the plasma membranes of some animals
A) enables the membrane to stay fluid more easily when cell temperature drops.
B) enables the animal to remove hydrogen atoms from saturated phospholipids.
C) enables the animal to add hydrogen atoms to unsaturated phospholipids.
D) makes the membrane less flexible, allowing it to sustain greater pressure from within the cell.
E) makes the animal more susceptible to circulatory disorders.
4) A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and
mitochondria. It could be a cell from
A) a bacterium.
B) an animal, but not a plant.
C) a plant, but not an animal.
D) a plant or an animal.
E) any kind of organism.
5) Which of the following statements describes the results of this reaction?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
A) C6H12O6 is oxidized and O2 is reduced.
B) O2 is oxidized and H2O is reduced.
C) CO2 is reduced and O2 is oxidized.
D) C6H12O6is reduced and CO2 is oxidized.
E) O2 is reduced and CO2 is oxidized.
6) Which of the following are prokaryotic cells?
A) plants
B) fungi
C) bacteria
D) animals
E) B and C only
7) Of the following, which is probably the most common route for membrane flow in the endomembrane system?
A) Golgi → lysosome → ER → plasma membrane
B) tonoplast → plasma membrane → nuclear envelope → smooth ER
C) nuclear envelope → lysosome → Golgi → plasma membrane
D) rough ER → vesicles → Golgi → plasma membrane
E) ER → chloroplasts → mitochondrion → cell membrane
8) Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane
more fluid at lower temperatures?
A) The double bonds form a kink in the fatty acid tail, forcing adjacent lipids to be further apart.
B) Unsaturated fatty acids have a higher cholesterol content.
C) Unsaturated fatty acids permit more water in the interior of the membrane.
D) The double bonds block interaction among the hydrophilic head groups of the lipids.
E) The double bonds result in a shorter fatty acid tail.
9) Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
A) catalysis
B) metabolism
C) anabolism
D) dehydration
E) catabolism
10) The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
A) gains electrons and gains energy.
B) loses electrons and loses energy.
C) gains electrons and loses energy.
D) loses electrons and gains energy.
E) none of the above.
11) During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
A) transferred to ADP, forming ATP.
B) transferred directly to ATP.
C) retained in the pyruvate.
D) stored in the NADH produced.
E) used to phosphorylate fructose to form fructose-6-phosphate.
12) Cellular respiration harvests the most chemical energy from which of the following?
A) substrate-level phosphorylation
B) oxidative phosphorylation
C) converting oxygen to ATP
D) transferring electrons from organic molecules to pyruvate
E) generating carbon dioxide and oxygen in the electron transport chain
13) Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin
cycle?
A) CO2 and glucose
B) H2O and O2
C) ADP, Pi, and NADP+
D) electrons and H+
E) ATP and NADPH
14) Which of the following statements about the light reactions of photosynthesis are true?
A) The splitting of water molecules provides a source of electrons.
B) Chlorophyll (and other pigments) absorb light energy, which excites electrons.
C) ATP is generated by photophosphorylation.
D) Only A and C are true.
E) A, B, and C are true.
15. Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the
stroma. This damage will have the most direct effect on which of the following processes?
A) the splitting of water
B) the absorption of light energy by chlorophyll
C) the flow of electrons from photosystem II to photosystem I
D) the synthesis of ATP
E) the reduction of NADP+
16) The lowest level of biological organization that can perform all the activities required for life is the
A) organelle-for example, a chloroplast.
B) cell-for example, a skin cell.
C) tissue-for example, nervous tissue.
D) organ system-for example, the reproductive system.
E) organism-for example, an amoeba, dog, human, or maple tree.
17) Different atomic forms of an element containing the same number of protons but a different number of neutrons
are referred to as?
A) ions
B) isotopes
C) neutronic atoms
D) isomers
E) radioactive atoms
18) One liter of a solution of pH 2 has how many more hydrogen ions (H +) than 1 L of a solution of pH 6?
A) 4 times more
B) 400 times more
C) 4,000 times more
D) 10,000 times more
E) 100,000 times more
Figure 1
19) What is the name of the functional group shown in Figure 1?
A) carbonyl
B) ketone
C) aldehyde
D) carboxyl
E) hydroxyl
20) Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
A) Dehydration reactions assemble polymers, and hydrolysis breaks down polymers.
B) Hydrolysis only occurs in the urinary system, and dehydration reactions only occur in the digestive tract.
C) Dehydration reactions can occur only after hydrolysis.
D) Hydrolysis creates monomers, and dehydration reactions break down polymers.
E) A and C are correct.
Essay: Please feel free to draw your answers, and to use concise bullet points. Complete sentences are not
necessary.
1a. (5 pts) Explain why enzymes are so important in living organisms.
b. (7 pts) Detail their function, including inhibitors.
2(15 pts) a. What is the chemical equation for cellular respiration? ____________________________________
b. In the space below, draw a diagram of a mitochondria. Label and indicate specifically where the 3 main stages of
cellular respiration take place.
c. Show where each of the substances in the above equation come in to or are released from the steps of cellular
respiration in your drawing.
d. Draw in the 2 main electron carriers in the correct places you would find them in their reduced and oxidized
states (when they are carrying electrons and when they have given up their electrons).
e. Show in your diagram how and where ATP is produced, and reactants and products of ATP production.