Exam 2 (Chapters 6,7,10,11)

Question 1

During cellular respiration, all of the energy in a molecule of glucose is not converted into the energy stored in ATP. What happens to the remaining energy?

Answer 1

It is lost as heat

Question 2

Hexokinase is an enzyme that binds specifically to glucose and converts it into glucose 6-phosphate. However, hexokinase activity is suppressed by glucose 6-phosphate, which binds to hexokinase at a location that is different from the active site. This is an example of what?

Answer 2

Feedback Inhibition

Question 3

The amount of energy available to do work is called:

Answer 3

Free Energy

Question 4

Where is the energy stored in molecule of ATP?

Answer 4

In the bonds connecting the two terminal phosphate groups

Question 5

Why does a reaction with negative delta G take a long time to proceed in the absence of an enzyme?

Answer 5

A certain amount of activation energy is required for the reaction to proceed

Question 6

The synthesis of sugar molecules through the process of photosynthesis requires energy absorbed from sunlight. Bearing this in mind, what kind of reaction is photosynthesis?

Answer 6

Endergonic

Question 7

Many useful drugs are competitive inhibitors of specific enzymes, however drug-resistance mutations prevent the binding of these drugs. These types of mutations, in addition to preventing competitive inhibitor binding, can also reduce the activity of the enzyme. Why is that the case?

Answer 7

These mutations most likely change the shape of the active site of the enzyme

Question 8

Glycolysis is a metabolic process that is performed by all cells. However, not all cells use the Krebs cycle. What does this tell you about the evolution of these processes?

Answer 8

Glycolysis likely evolved prior to the Krebs cycle

Question 9

A new antibiotic has been developed that inhibits the activity of an enzyme by competitive inhibition. What effect will this have on the activation energy of the enzyme-catalyzed reaction?

Answer 9

The activation energy will be the same

Question 10

Glycolysis produces ATP by

Answer 10

Substrate-Level Phosphorylation

Question 11

What is the importance of fermentation to cellular metabolism?

Answer 11

It oxidizes NADH to NAD+ in the absence of O2.

Question 12

At what specific point in the cellular respiration process has glucose been broken down completely from a six carbon molecule to 6 molecules of CO2?

Answer 12

During the second oxidation in the Krebs Cycle

Question 13

What happens to the oxygen that is used in cellular respiration?

Answer 13

It is reduced to form water

Question 14

When amino acids are degraded in cells, into what intermediate(s) of the aerobic respiration process are the carbon skeletons of amino acids primarily converted?

Answer 14

Pyruvate and Krebs cycle intermediates

Question 15

The oxidized form of the most common electron carrier found in both glycolysis and the Kreb’s cycle is

Answer 15

NAD+

Question 16

When lipids are used for energy in cellular respiration, they are converted into what?

Answer 16

Acetyl-CoA

Question 17

What must happen to amino acids before they can be used in catabolic reactions?

Answer 17

They must be deaminated

Question 18

IN some situations, mitosis occurs without cytokinesis occurring. This will result in:

Answer 18

Cells with more than one nucleus

Question 19

Animal cells typically achieve cytokinesis by:

Answer 19

Forming a cleavage furrow

Question 20

Stage of the cell cycle is characterized by growth and it contains a checkpoint to verify that the DNA has been replicated prior to cell division

Answer 20

G2

Question 21

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 7 picograms of DNA per nucleus. Those cells would have ______ picograms at the end of the S phase and _______ picograms at the end of G2.

Answer 21

14

14

Question 22

A cell in which of the following phases would have the least amount of DNA?

Answer 22

Anaphase

Question 23

The DNA content of diploid cell in the G1 phase of the cell cycle is measure. If the DNA content is x, then the DNA content of the same cell at metaphase of meiosis I would be what?

Answer 23

2x

Question 24

The DNA content of a diploid cell in the G1 phase of the cell cycle is measured. If the DNA content is x, then the DNA content at metaphase of meiosis II would be what?

Answer 24

x

Question 25

The portion of the cell cycle when the cell is growing and does not contain a replicated genome is referred to as:

Answer 25

G1

Question 26

What structures are held together by cohesion proteins?

Answer 26

Sister Chromatids

Question 27

How does the organization of the bacterial genome differ from the organization of the eukaryotic genome?

Answer 27

Most bacterial chromosomes are circular and the eukaryotic chromosome are not

Question 28

A new drug that impedes the binding of lavin adenine dinucleotide to electrons, resulting in less FADH2. The drug would be effective in _________

Answer 28

Weight Loss

Question 29

The chemical 2,4 dinitrophenol (DNP) is used in the manufacturing of dyes, wood preservatives, and other products. Products containing DNP are toxic because DNP uncouples oxidative phosphorylation. In a cell exposed to DNP, how many net ATP molecules would be generated per molecule of glucose?

Answer 29

2

Question 30

The enzymes of the Krebs cycle are located in the

Answer 30

Matrix of the Mitochondria

Question 31

The correct sequence for glucose catabolism is:

Answer 31

Glycolysis
Pyruvate
Acetyl CoA
Krebs Cycle
Electron Transport Chain

Question 32

Why are the components of the electron transport chain embedded in the inner mitochondrial membrane rather than floating freely in the mitochondrial matrix?

Answer 32

To generate and maintain the proton gradient essential for ATP production

Question 33

In prophase, ribosomal RNA synthesis stops when the chromosomes condense, and as a result:

Answer 33

Nucleolus disappears

Question 34

What stage of mitosis is characterized by the alignment of the chromosomes in a ring along the inner circumference of the cell?

Answer 34

Metaphase

Question 35

If there are 32 sister chromatids in normal somatic cell, how many chromosomes are there?

Answer 35

16

Question 36

If a drug that inhibited transport from the trans face of the Golgi was applied to plant cells, which stage of the cell cycle would be directly affected?

Answer 36

Cytokinesis

Question 37

What is the function of the kinetochore?

Answer 37

Connect the centromere to microtubules

Question 38

All 39 pairs of sister chromatids in a dog cell (n=39) segregate normally during meiosis II except for one pair of sister chromatids in one of the cells, which undergoes nondisjunction during meiosis II. At the end of meiosis II, there will be:

Answer 38

3 cells with 39 chromosomes, 1 cell with 38

Question 39

If there were no suppression DNA replication between meiotic division but cytokinesis proceeded normally, what is the most likely outcome of meiosis?

Answer 39

4 Diploid Cells

Question 40

Which structures indicate where crossing over has occurred?

Answer 40

Chiasmata