Final part 3

Question 1

when substrate binds to an enzyme, the enzyme changes shape this reaction is called:

Answer 1

induced fit

Question 2

Which carries vesicles by “walking” along microtubules of the cytoskeleton?

Answer 2

motor protein

Question 3

What are proteins that are tagged with ubiquitin and taken into its core and degraded?

Answer 3

proteasome

Question 4

In the following reaction, which molecule is the reducing agent? Glyceraldehyde triphosphate + NAD+ → diphosphoglycerate + NADH + H+

Answer 4

glyceraldehyde triphosphate

Question 5

Fatty acids can enter the metabolic pathway at which point?

Answer 5

Formation of Acetyl coA

Question 6

The oxygen consumed during cellular respiration is involved directly in which process or event?

Answer 6

Accepting electrons at the end of the electron transport chain

Question 7

An enzyme catalyzes a reaction by:

Answer 7

lowering the activation energy of a reaction

Question 8

At high concentrations, ATP binds to the allosteric site of phosphofructokinase, which catalyzes the third step in glycolysis. Binding of ATP causes a conformational change that halts enzyme activity and prevents overproduction of ATP. Which of the following best describes the type of enzymatic reaction taking place?

Answer 8

feedback inhibition

Question 9

In the following reaction, which molecule is reduced?
6 CO2 + 6 H2O + light energy -> C6H12O6 + 6 O2

Answer 9

CO2

Question 10

The first enzyme in glycolysis which catalyzes the phosphorylation of glucose, binds glucose and ATP:

Answer 10

Hexokinase

Question 11

In the formation of purines (components of nucleic acids), tetrahydrofolate is very important. Tetrahydrofolate is formed from the reaction of dihydrofolate with dihydrofolate reductase (DHFR). To treat leukemia, scientists developed a drug called methotrexate that prevents cancer cells from forming purines. Methotrexate binds to DHFR and prevents formation of nucleic acids by cancer cells but does not alter conformation of DHFR.
WHAT IS THE SUBSTRATE IN THIS REACTION AND WHAT IS THE BEST CATEGORY FOR THE REACTION INVOLVING METHOREXATE?

Answer 11

1. dihydrofolate
2. competitive inhibition reaction

Question 12

In the energy-yielding or payoff phase of glycolysis, energy is extracted in the form of:

Answer 12

NADH and ATP

Question 13

Which is the major source of electrons for the electron transport chain?

Answer 13

NADH

Question 14

In the citric acid cycle, what is the molecule that binds to acetyl CoA?

Answer 14

Oxaloacetate

Question 15

Which kind of metabolic poison would most directly interfere with glycolysis?

Answer 15

one that closely mimics the structure of glucose but is not metabolized

Question 16

During fermentation, which molecule must be oxidized so that glycolysis can keep running?

Answer 16

NADH

Question 17

Which of the following have to occur in order to form acetyl CoA during cellular respiration?

Answer 17

oxidation of pyruvate AND the presence of oxygen

Question 18

What is the first product of the Krebs cycle?

Answer 18

citrate

Question 19

If NADPH builds up during photosynthesis what is most likely to occur?

Answer 19

cyclic electron glow

Question 20

if rubisco is exposed to high concentrations of oxygen, what may happen?

Answer 20

photorespiration, rubisco will bind oxygen instead of CO2, carbohydrate production will be severely affected, and the plant will waste energy

Question 21

During the light-dependent reactions, a high concentration of H+ is

Answer 21

found in the thylakoid lumen AND used to establish the proton motive force

Question 22

During non-cyclic electron flow of the light-dependent reactions, which molecule is the final acceptor of the high-energy electrons?

Answer 22

NADP+

Question 23

Plants that appear green to the human eye:

Answer 23

reflect green color, are absorbing other colors such as red and blue, in of the visible light spectrum for the purpose of photosynthesis AND are not absorbing the green light portion of the visible light spectrum for the purposes of photosynthesis

Question 24

When electrons in primary pigment molecules become photoexcited, what happens?

Answer 24

electrons are boosted from a ground state to a higher energy state AND electrons are captured by the primary electron acceptor before they go back to ground state

Question 25

When oxygen is produced during photosynthesis, it is a byproduct of the:

Answer 25

oxidation of H2O

Question 26

In C-4 plants, CO2 will dissociate from which molecule within the bundle sheath layer?

Answer 26

Malate

Question 27

Photosystems are found in which specific structure?

Answer 27

Thylakoid membranes

Question 28

Stacks of thylakoids are known as

Answer 28

Grana

Question 29

The light-dependent reactions of photosynthesis occur in the __________of the chloroplast and the light-independent reactions occur in the ____________of the chloroplast.

Answer 29

thylakoid membrane; stroma

Question 30

The light-independent reactions are powered by ________and __________, which are the products of the light-dependent reactions.

Answer 30

NADPH and ATP

Question 31

During the light-dependent reactions of photosynthesis, hydrogen is pumped against its concentration gradient from the _________ to the ___________

Answer 31

Stroma; Lumen

Question 32

Muscle cells in oxygen deprivation convert pyruvate to ______

Answer 32

Lactate/ lactic acid

Question 33

In order to power the pumping of hydrogen against its concentration gradient during cell respiration, NADH and FADH2 donate __________to the ______________.

Answer 33

electrons; ETC

Question 34

The final electron acceptor in the cellular respiration pathway is: _________________

Answer 34

oxygen