Bio Exam #2: Practice Test

20) During cellular respiration, acetyl CoA accumulates in which location? A) cytosol B) mitochondrial outer membrane C) mitochondrial inner membrane D) mitochondrial intermembrane space E) mitochondrial matrix

E

21) Starting with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells? A) 4 B) 8 C) 16 D) 32 E) 64

E

35) At which phase are centrioles beginning to move apart in animal cells? A) telophase B) anaphase C) prometaphase D) metaphase E) prophase

E

14) The proteins of the electron transport chain active in the light-dependent reactions ________. A) are membrane proteins present in the thylakoid B) are free proteins present in the thylakoid lumen C) are considered to be part of the reaction center of photosystem I D) absorb the same wavelengths of light as their associated chlorophylls

A

16) In autumn, the leaves of deciduous trees change colors. This is because chlorophyll is degraded and ________. A) carotenoids and other pigments are still present in the leaves B) the degraded chlorophyll changes into many other colors C) water supply to the leaves has been reduced D) sugars are sent to most of the cells of the leaves

A

1) Which of the following statements about NAD+ is TRUE? A) NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. B) NAD+ has more chemical energy than NADH. C) NAD+ is oxidized by the action of hydrogenases. D) NAD+ can donate electrons for use in oxidative phosphorylation. E) In the absence of NAD+, glycolysis can still function.

A

10) Which observation would provide supporting evidence for the chemiosmosis model of ATP formation? a. A) The intermembrane space (IMS) has a lower pH (i.e., more acidic) than the matrix. b. B) The intermembrane space (IMS) has a higher pH than the matrix. c. C) Electrons diffuse through ATP synthase. d. D) NADH donates protons to the electron transport chain.

A

4) Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent? A) electron transport B) glycolysis C) the citric acid cycle D) oxidative phosphorylation E) chemiosmosis

B

27) If a cell has accumulated DNA damage, it is unlikely to ________. A) pass the G2 checkpoint B) activate DNA repair mechanisms C) enter G1 from mitosis D) synthesize cyclin-dependent kinases

A

28) The first gap in the cell cycle (G1) corresponds to ________. A) normal growth and cell function B) the phase in which DNA is being replicated C) the beginning of mitosis D) the phase between DNA replication and the M phase

A

36) Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells? A) kinetochores B) Golgi-derived vesicles C) actin and myosin D) centrioles and centromeres E) tubulin and dynein

B

11) The process of photosynthesis probably originated ________. A) in plants B) in prokaryotes C) in fungi D) three separate times during evolution

B

12) When oxygen is released as a result of photosynthesis, it is a direct by-product of ________. A) reducing NADP+ B) splitting water molecules C) chemiosmosis D) the electron transfer system of photosystem I E) the electron transfer system of photosystem II

B

13) Chlorophylls absorb most light in which colors of the visible range? A) green and blue B) blue and red C) green and red D) violet and red

B

17) Why are there several structurally different pigments in the reaction centers of photosystems? A) Excited electrons must pass through several pigments before they can be transferred to electron acceptors of the electron transport chain. B) This arrangement enables the plant to absorb light energy of a variety of wavelengths. C) They enable the plant to absorb more photons from light energy, all of which are at the same wavelength. D) They enable the reaction center to excite electrons to a higher energy level.

B

2) What is the term for metabolic pathways that release stored energy by breaking down complex molecules? A) anabolic pathways B) catabolic pathways C) fermentation pathways D) thermodynamic pathways E) bioenergetic pathways

B

26) Which of the following does NOT occur during mitosis? A) condensation of the chromosomes B) replication of the DNA C) separation of sister chromatids D) spindle formation E) separation of the spindle poles

B

32) In human and many other eukaryotic species' cells, the nuclear membrane has to disappear to permit ________. A) cytokinesis B) the attachment of microtubules to kinetochores C) the splitting of the centrosomes D) the disassembly of the nucleolus

B

33) If there are 20 chromatids in a cell, how many centromeres are there? A) 10 B) 20 C) 30 D) 40 E) 80

B

34) Mitosis separates chromosomes. Cytoplasm is divided between two daughter cells by ________. A) cloning B) cytokinesis C) binary fission D) the formation of kinetochores

B

19) In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during ________. A) photosynthesis only B) respiration only C) photosynthesis and respiration D) neither photosynthesis nor respiration E) photorespiration only

C

24) In eukaryotic cells, chromosomes are composed of ________. A) DNA and RNA B) DNA only C) DNA and proteins D) DNA and phospholipids

C

18) The figure shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different? A) Green and yellow wavelengths inhibit the absorption of red and blue wavelengths. B) Bright sunlight destroys photosynthetic pigments. C) Oxygen given off during photosynthesis interferes with the absorption of light. D) Other pigments absorb light in addition to chlorophyll a. E) Aerobic bacteria take up oxygen, which changes the measurement of the rate of

D

25) The mitotic spindle is a microtubular structure that is involved in ________. A) splitting of the cell (cytokinesis) following mitosis B) triggering the compaction and condensation of chromosomes C) dissolving the nuclear membrane D) separation of sister chromatids

D

3) What kind of molecules serve as electron acceptors in cellular respiration? A) water B) polar molecules C) molecules with high potential energy D) molecules with low potential energy E) molecules in an excited state

D

5) Following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO2 with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is in the form of A) acetyl CoA B) glucose C) pyruvate D) NADH

D

15) What is the primary function of the Calvin cycle? A) using ATP to release carbon dioxide B) using NADPH to release carbon dioxide C) splitting water and releasing oxygen D) transporting RuBP out of the chloroplast E) synthesizing simple sugars from carbon dioxide

E