BIO 1510 Exam II Study Notes

BIO 1510 Exam II ─ Study Notes

Questions from the Exam

Question 1

  • Topic: Light Reactions of Photosynthesis

    • Question: The final acceptor of electrons in the light reactions of photosynthesis is:

    • Options:

    • A. NADPH

    • B. O2

    • C. NADP+

    • D. ATP

Question 2

  • Topic: Fermentation Pathways

    • Question: What is the main purpose of the reactions in a fermentation pathway?

    • Options:

    • A. to synthesize pyruvate from lactate

    • B. to synthesize electron acceptors, so cellular respiration can continue

    • C. to generate NAD+ from NADH, so glycolysis can continue

    • D. to generate NADH from NAD+, so electrons can be donated to the electron transport chain

Question 3

  • Topic: Alcoholic Fermentation

    • Question: During alcoholic fermentation, the molecules pyruvate and acetaldehyde are, respectively:

    • Options:

    • A. decarboxylated and phosphorylated

    • B. decarboxylated and reduced

    • C. decarboxylated and oxidized

    • D. reduced and decarboxylated

Question 4

  • Topic: Metabolic Pathways

    • Statement: The Krebs cycle is a catabolic pathway, while the Calvin cycle is an anabolic pathway.

    • True/False Options:

    • A. True

    • B. False

Question 5

  • Topic: Substrate-Level Phosphorylation

    • Question: When substrate-level phosphorylation occurs, it means that:

    • Options:

    • A. ATP is converted into ADP and phosphate group

    • B. ADP is converted into ATP by addition of a phosphate group

    • C. NADH is converted into NAD+ and H

    • D. NAD+ is converted into NADH

Question 6

  • Topic: Cellular Respiration in Prokaryotes

    • Question: If a prokaryotic organism is incubated under aerobic conditions, how many molecules of ATP would be produced upon the complete oxidation of one molecule of glucose?

    • Options:

    • A. 32

    • B. 30

    • C. 28

    • D. 26

Question 7

  • Topic: Structure of Chloroplasts

    • Question: What is the stroma of a chloroplast?

    • Options:

    • A. the pieces of membrane that connect grana

    • B. the interior of thylakoid

    • C. the fluid inside the chloroplast but outside of thylakoids

    • D. the inner membrane

Question 8

  • Topic: Amino Acid Phosphorylation

    • Question: Tyrosine kinase phosphorylates a threonine amino acid.

    • True/False Options:

    • A. True

    • B. False

Question 9

  • Topic: Carbon Fixation

    • Question: What does it mean to say that CO2 becomes "fixed"?

    • Options:

    • A. it acts as an electron donor

    • B. it becomes bonded to an organic compound

    • C. it is released during cellular respiration

    • D. it acts as an electron acceptor

Question 10

  • Topic: Photosystems

    • Question: What does it mean to say that photosystem II “splits” water?

    • Options:

    • A. water is reduced to yield H2 gas

    • B. a condensation reaction occurs

    • C. water is broken into monomers

    • D. water is oxidized to yield H+, electrons, and O2

Question 11

  • Topic: Regulation of Cellular Respiration

    • Question: Cellular respiration is controlled by:

    • Options:

    • A. citric acid that inhibits the production of fructose 1,6-biphosphate

    • B. ATP that inhibits an enzyme in the endergonic phase of glycolysis

    • C. NADH that inhibits an enzyme in the Krebs cycle

    • D. A and B

Question 12

  • Topic: Plastocyanin

    • Question: The electrons received by plastocyanin (pC) have more energy than the electrons received by ferredoxin (Fd).

    • True/False Options:

    • A. True

    • B. False

Question 13

  • Topic: Enzyme Functionality

    • Question: Which of the following enzymes would be expected to work best in a basic environment?

    • Options:

    • A. trypsin

    • B. pepsin

    • C. digestive enzymes found in lysosomes

    • D. A and C

Question 14

  • Topic: Signal Amplification

    • Question: When one ligand binds to one receptor, the signal can be amplified and affect multiple processes in a cell if kinases are activated.

    • True/False Options:

    • A. True

    • B. False

Question 15

  • Topic: Signaling Types

    • Question: Endocrine signaling involves the release of neurotransmitters.

    • True/False Options:

    • A. True

    • B. False

Question 16

  • Topic: Energy Production in Mitochondria

    • Question: All of the following are key processes in the production of energy in the mitochondria EXCEPT:

    • Options:

    • A. electron transport chain

    • B. oxidative phosphorylation

    • C. the Krebs cycle

    • D. glycolysis

Question 17

  • Topic: Competitive Inhibition

    • Question: While conducting an experiment, you realize that a competitive inhibitor was interfering with your reaction. To overcome this problem, you:

    • Options:

    • A. decrease the concentration of the correct substrate in the reaction

    • B. increase the concentration of the correct substrate in the reaction

    • C. add an allosteric activator to the reaction

    • D. add a non-competitive inhibitor to the reaction

Question 18

  • Topic: Organism Classification

    • Question: Organisms that can manufacture their own chemical energy sources are called chemotrophs.

    • True/False Options:

    • A. True

    • B. False

Question 19

  • Topic: Regulation of Enzymes

    • Question: In order to study the mechanism in which pyruvate is converted to acetyl-CoA, the enzyme responsible for this conversion is most likely to be found in the:

    • Options:

    • A. cytoplasm of the cell

    • B. mitochondrial matrix

    • C. endoplasmic reticulum

    • D. inner mitochondrial membrane

Question 20

  • Topic: C4 vs. CAM Plants

    • Question: C4 plants differ from CAM plants in that, in C4 plants CO2 fixation and Calvin cycle occur at different times of day.

    • True/False Options:

    • A. True

    • B. False

Question 21

  • Topic: Thermodynamics

    • Question: According to the second law of thermodynamics:

    • Options:

    • A. free energy is available to do work

    • B. energy may be changed from one form to another but it is neither created nor destroyed

    • C. much of the work that an organism does is mechanical work

    • D. the disorder of the universe is increasing

Question 22

  • Topic: Products of Light Reactions

    • Question: What do the light reactions of photosynthesis produce?

    • Options:

    • A. ATP and NADPH

    • B. glyceraldehyde 3 phosphate (G3P)

    • C. ribulose 1,5-biphosphate (RuBP)

    • D. plastoquinone (pQ)

Question 23

  • Topic: Enzyme Types

    • Question: The enzyme responsible for the conversion of fructose 6-phosphate to fructose 1,6-biphosphate is a:

    • Options:

    • A. isomerase

    • B. dehydrogenase

    • C. kinase

    • D. synthetase

Question 24

  • Topic: Effect of Drugs on Enzymes

    • Question: The drug known as Viagra helps smooth muscles relax by inhibiting the enzyme phosphofructokinase.

    • True/False Options:

    • A. True

    • B. False

Question 25

  • Topic: Types of Inhibitors

    • Question: Which inhibitor binds to the active site of an enzyme?

    • Options:

    • A. noncompetitive

    • B. competitive

    • C. coenzyme

    • D. allosteric

Question 26

  • Topic: Electron Transport Chain in Animal Cells

    • Question: In animal cells, the electron transport chain consists of all of the following EXCEPT:

    • Options:

    • A. cytochrome C (C)

    • B. ubiquinone (Q)

    • C. cytochrome oxidase complex

    • D. NADP reductase

Question 27

  • Topic: Chemiosmosis in Animal Cells

    • Question: In animal cells, during the process of chemiosmosis, ATP is produced as H+ move from to , passing through __.

    • Options:

    • A. the cytoplasm, the matrix, the electron transport chain

    • B. the matrix, the intermembrane space, ATP synthase

    • C. the matrix, the cytoplasm, the Krebs cycle

    • D. the intermembrane space, the matrix, ATP synthase

Question 28

  • Topic: ATP Production Comparison

    • Question: FADH2 results in more ATP production when compared to NADH.

    • True/False Options:

    • A. True

    • B. False

Question 29

  • Topic: Final Acceptors of Electrons

    • Question: In the last stage of aerobic respiration, ___ is the final acceptor of electrons.

    • Options:

    • A. H2

    • B. O2

    • C. NADH

    • D. H2O

Question 30

  • Topic: Leaf Structures and Functions

    • Question: Which of the following leaf structures is not matched to its correct function?

    • Options:

    • A. guard cells—control the size of the stroma

    • B. stomata—allow gas exchange

    • C. cuticle—prevents water loss

    • D. all of the above are matched correctly

Question 31

  • Topic: Immune System Signaling

    • Question: In order to destroy invading organisms, the T cells of our immune system release growth factors for their own receptors. This is an example of:

    • Options:

    • A. contact-dependent signaling

    • B. autocrine signaling

    • C. paracrine signaling

    • D. endocrine signaling

Question 32

  • Topic: ATP Production in Glucose Breakdown

    • Question: Of the 32 ATP molecules that are produced during the complete breakdown of glucose, most are due to the action of oxidative phosphorylation.

    • True/False Options:

    • A. True

    • B. False

Question 33

  • Topic: Estrogen Binding

    • Question: Estrogen is bound to receptor proteins in the cytoplasm of target cells. This binding is necessary for:

    • Options:

    • A. the transport of the hormone molecule through an aqueous environment

    • B. the action of estrogen at receptor sites in an aqueous environment

    • C. the action of estrogen and its receptor in the nucleus

    • D. the transport of hormone molecule through nonpolar liquids

Question 34

  • Topic: Diet and Body Fat

    • Question: In order to lose weight and reduce body fat, a friend of yours decided to eliminate all fat from their diet, while consuming unrestricted amounts of carbohydrates. This approach, however, would be unsuccessful at reducing body fat because excess acetyl-CoA will undergo deamination to produce body fat.

    • True/False Options:

    • A. True

    • B. False

Question 35

  • Topic: Electron Transport Chain Mechanics

    • Question: As electrons move through the H+ pumps of the electron transport chain in animal cells, each intermediate carrier molecule is:

    • Options:

    • A. reduced by the preceding molecule and oxidized by the following molecule.

    • B. oxidized by the preceding molecule and reduced by the following molecule.

    • C. reduced by both the preceding and the following molecules.

    • D. oxidized by both the preceding and the following molecules.

Question 36

  • Topic: Feedback Inhibition

    • Question: What is feedback inhibition?

    • Options:

    • A. when lack of an appropriate electron acceptor makes an electron transport chain stop

    • B. when an enzyme that is active early in a metabolic pathway is inhibited by a product of the pathway

    • C. when ATP synthase reverses and begins pumping H+ out of the mitochondrial matrix

    • D. when cellular respiration stops and fermentation begins

Question 37

  • Topic: Cellular Communication Mechanisms

    • Question: Communication between cells can occur by all of the following basic mechanisms EXCEPT:

    • Options:

    • A. endocrine signaling

    • B. intracellular signaling

    • C. contact-dependent

    • D. synaptic signaling

Question 38

  • Topic: Products of Light-Dependent Reactions

    • Question: The products of light-dependent reactions are used to:

    • Options:

    • A. convert 3-phosphoglycerate (PGA) to glyceraldehyde 3-phosphate (G3P)

    • B. cause rubisco to fix CO2

    • C. cause electrons to move along their pathways

    • D. reform the photosynthesis

Question 39

  • Topic: Yield from Glucose Breakdown

    • Question: The net yield from one glucose molecule going through glycolysis, pyruvate oxidation, and the Krebs cycle is molecules of NADH and __ molecules of FADH2.

    • Options:

    • A. 8 and 2

    • B. 10 and 2

    • C. 3 and 1

    • D. 6 and 2

Question 40

  • Topic: Coenzymes

    • Question: NAD+, FAD, and NADP+ are .

    • Options:

    • A. metal ions

    • B. coenzymes

    • C. allosteric enzymes

    • D. A and B

Key Concepts and Explanations

Light Reactions

  • Function: Transfer of electrons during photosynthesis, with NADP+ as the final electron acceptor which undergoes reduction to NADPH.

Fermentation Pathways

  • Importance: Generate NAD+ from NADH, enabling glycolysis to continue producing ATP in anaerobic conditions, thus supporting cellular metabolism.

Alcoholic Fermentation

  • Process Overview: Involves decarboxylation of pyruvate to acetaldehyde followed by its reduction to ethanol.

Metabolic Pathways

  • Krebs Cycle: Catabolic pathway that breaks down molecules for energy; contrasted with the anabolic Calvin cycle that synthesizes glucose.

Substrate-Level Phosphorylation

  • Definition: A metabolic process that generates ATP directly from ADP and a phosphate group in energy-yielding pathways.

Aerobic Respiration in Prokaryotes

  • ATP Yield: Typically results in 30 to 32 ATP per glucose molecule during complete oxidation under aerobic conditions.

Chloroplast Structure

  • Stroma: Refers to the fluid matrix inside the chloroplast where the Calvin cycle occurs, separate from thylakoid membranes.