2.2: Glucose Metabolism

Question 1

What molecule is this: C6H12O6

Answer 1

Glucose

Question 2

The complete catabolism of a single molecule of glucose (C6H12O6) yields up to how molecules of ATP?

Answer 2

38 ATP

Question 3

Glycolysis is the first step of the Glucose Catabolism process (energetically speaking) and yields how many molecules of ATP?

Answer 3

2 ATP

Question 4

Glycolysis begins with the breakdown of a single molecule of ______.

Answer 4

Glucose

Question 5

______ begins with the breakdown of a single molecule of glucose.

Answer 5

Glycolysis

Question 6

In Glycolysis, any molecules present and involved at the beginning of a chemical reaction are called ______.

Answer 6

Reactants

Question 7

When writing out chemical reactions, the reactants are always located to the ______ of the reaction arrow.

Answer 7

Left

Question 8

When writing out chemical reactions, the ______ are always located to the left of the reaction arrow.

Answer 8

reactants

Question 9

In addition to glucose, two electron carrier molecules of the coenzyme ______ as well as an initial input of two molecules of ATP are present as reactants.

Answer 9

nicotinamide adenine dinucleotide (NAD)

Question 10

What is the purpose of the initial input of two molecules of ATP as reactants in Glycolysis?

Answer 10

This initial input of ATP is quickly used to phosphorylate glucose and is an essential step for initiating glycolysis.

Question 11

What does NAD stand for?

Answer 11

It stand for the coenzyme, Nicotinamide Adenine Dinucleotide (NAD)

Question 12

What does G6P stand for and what is it?

Answer 12

Glucose-6-Phosphate

Its is the Phosphorylation of glucose.

Question 13

Phosphorylation of glucose both ___1___ and ___2___.

Answer 13

1. prevents glucose from diffusing out of the cell
2. serves as the signal molecule to the cell that glycolysis is about to begin

Question 14

______ both prevents glucose from diffusing out of the cell and serves as the signal molecule to the cell that glycolysis is about to begin.

Answer 14

Phosphorylation of glucose (glucose-6-phosphate, aka G6P)

Question 15

Once glycolysis is complete, several products (molecules located to the right of the arrow) are produced and include:

Answer 15

2 pyruvate molecules, 2 NADH molecules, and 4 ATP.

Question 16

Finish:
Glucose + 2 NAD+ + [2 ADP + 2 Pi]→

Answer 16

2 Pyruvate + 2 NADH + 2 ATP + 2 H+

Question 17

Finish:
→2 Pyruvate + 2 NADH + 2 ATP + 2 H+

Answer 17

Glucose + 2 NAD+ + [2 ADP + 2 Pi]

Question 18

___1___ are always located to the left of the reaction arrow while ___2___ are always located to the right of the reaction arrow.

Answer 18

1. Reactant(s)
2. Products(s)

Question 19

______ plays a vital role in generating and maintaining energy for the cell.

Answer 19

NAD/NADH

Question 20

In order for glycolysis to continue to proceed, microorganisms must convert ___1___ back to ___2___.

Answer 20

1. NADH
2. NAD+

Question 21

There are two main strategies utilized by cells to replenish the supply of NAD+: fermentation or respiration

Answer 21

1. fermentation
2. respiration

Question 22

______ is an anaerobic (absence of oxygen) process in which NADH is converted back to NAD+ while pyruvate is converted to a waste byproduct, commonly lactic acid or ethanol, to be eliminated from the cell.

Answer 22

Fermentation

Question 23

Fermentation is an ___1___ process in which ___2___ is converted back to ___3___ while ___4___ is converted to a waste byproduct, commonly ___5___ or ___6___, to be eliminated from the cell.

Answer 23

1. anaerobic (absence of oxygen)
2. NADH
3. NAD+
4. pyruvate
5. lactic acid
6. ethanol

Question 24

Anaerobic means what?

Answer 24

Absence of oxygen

Question 25

Absence of oxygen means to be what?

Answer 25

Anaerobic

Question 26

While ______ may resupply the levels of NAD+ in a cell, it cannot oxidize pyruvate, so it does not produce any additional energy (ATP) for the cell.

Answer 26

Fermentation

Question 27

While fermentation may resupply the levels of ___1___ in a cell, it cannot ___2___ pyruvate, so it does not produce any additional ___3___ for the cell.

Answer 27

1. NAD+
2. oxidize
3. energy (ATP)

Question 28

______ is a more efficient aerobic process used by microorganisms to produce energy.

Answer 28

Respiration

Question 29

Respiration is a more efficient ______ process used by microorganisms to produce energy.

Answer 29

Aerobic

Question 30

Since most of the potential energy from glucose is still locked in the form of pyruvate following the initial stage of glycolysis, ______ is the process of unlocking that energy.

Answer 30

Respiration

Question 31

The central pathway of respiration is called the ___1___, also known as the ___2___; named after the 1953 Noble Prize-winning scientist ___3___.

Answer 31

1. tricarboxylic acid (TCA) cycle
2. Krebs Cycle
3. Hans Krebs

Question 32

Respiration requires an additional coenzyme similar to NAD called ______.

Answer 32

flavin adenine dinucleotide (FAD)

Question 33

What does FAD stand for?

Answer 33

flavin adenine dinucleotide (FAD)

Question 34

What does TCA stand for?

Answer 34

Tricarboxylic Acid (TCA) cycle

Question 35

At its conclusion, the TCA cycle produces ___1___ ATP in total (one for each ___2___ processed) and an abundance of reduced electron carriers: ___3___ and ___4___.

Answer 35

1. 2
2. pyruvate
3. NADH
4. FADH2

Question 36

The production of these reduced electron carriers (NADH and FADH2) is the primary function of the ___1___, as the transfer of these electrons will fuel the generation of ATP via the ___2___.

Answer 36

1. TCA cycle
2. electron transport system

Question 37

The ___1___, also referred to as the ___2___, is a continuation of cellular respiration and can proceed either aerobically or anaerobically.

Answer 37

1. electron transport system
2. electron transport chain

Question 38

The electron transport system, also referred to as the electron transport chain, is a continuation of cellular respiration and can proceed either ___1___ or ___2___.

Answer 38

1. aerobically
2. anaerobically

Question 39

___1___ respiration is less efficient and yields fewer ATP molecules than ___2___ respiration.

Answer 39

1. anaerobic
2. aerobic

Question 40

As electrons are transferred from NADH/FADH2 to terminal electron acceptors (O2; aerobic respiration), energy is released and captured by electron acceptor proteins located in the inner membrane of ______.

Answer 40

mitochondria.

Question 41

The ______ drives H+ back through the ATP synthase complex, also located in the membrane, resulting in the production of up to 34 molecules of ATP.

Answer 41

proton motive force

Question 42

The proton motive force drives ___1___ back through the ___2___, also located in the ___3___, resulting in the production of up to ___4___ molecules of ATP.

Answer 42

1. H+
2. ATP synthase complex
3. membrane
4. 34

Question 43

In summary, cells require ___1___ to survive. The breakdown of ___2___, an abundant and common source of energy, is often utilized by various microbes. Under ___3___, the complete catabolism of glucose yields ___4___ ATP from glycolysis, ___5___ ATP from the TCA cycle, and ___6___ ATP from the electron transport system, for a total of ___7___ ATP from a single glucose molecule.

Answer 43

1. ATP
2. glucose
3. aerobic conditions
4. 2
5. 2
6. 34
7. 38

Question 44

Were does glycolysis occur?

Answer 44

The cytoplasm

Question 45

______ in an anaerobic reaction taking place in the cytoplasm.

Answer 45

Glycolysis

Question 46

Glycolysis has two major phases. What are they?

Answer 46

Energy investment phase and energy payoff phase