Lecture 12

Question 1

Hydrogen pairs with their electrons are delivered to ETC carrier molecules by

Answer 1

the coenzymes NAD and FAD (their reduced forms)

Question 2

The electrons flow from one carrier molecule to another in a series of

Answer 2

oxidation and reduction reactions

Question 3

In aerobic respiration what is the

final hydrogen/electron acceptor

Answer 3

oxygen

Question 4

As these reactions proceed ATP is generated and released incrementally by a process known as

Answer 4

chemiosmosis

Question 5

cytochromes

Answer 5

Many of the ETC intermediates are iron containing

compounds known as cytochromes

Question 6

For every 2H (hydrogen pair) delivered to the ETC on NAD how many ATPs are manufactured

Answer 6

3 ATPs are manufactured

Question 7

For every 2H delivered to the ETC on FAD on many ATPs are manufactured

Answer 7

2 ATPs are manufactured

Question 8

The vast majority of the cells ATPs are manufactured in

Answer 8

the ETC

Question 9

The ATP is produced here by a process known as

Answer 9

oxidative phosphorylation

Question 10

ETC is sometimes referred to as

Answer 10

the Respiratory Chain or the Cytochrome Chain.

Question 11

In anaerobic respiration the final hydrogen/electron acceptor is

Answer 11

In anaerobic respiration there are inorganic final hydrogen/electron acceptors other than oxygen that
are driving the oxidation and reduction reactions

Question 12

Why are there fewer ATP generated in anaerobic

Answer 12

However, since the pull of these other inorganic acceptors is less than oxygen, there are fewer ATP’s generated.

Question 13

Glycolysis total ATP

Answer 13

2 ATPs by substrate level phosphorylation

6 ATPs by oxidative phosphorylation in ETC. (2 NAD each with a 2H are produced) Note, each 2H carried
to ETC on NAD yields 3 ATPs. 2 X 3 = 6

Question 14

Intermediate or Preparatory Step total ATP

Answer 14

6 ATPs by oxidative phosphorylation in ETC. (An NAD with a 2H is produced for each pyruvic acid that is
converted into an acetyl group. Two acetyl groups are made from each glucose, as two pyruvic acids are
made from each glucose).

Question 15

Krebs Cycle total ATP

Answer 15

2 ATPs by substrate level phosphorylation
18 ATPs by oxidative phosphorylation in ETC. (6 2H are delivered to ETC on NAD per glucose).
4 ATPs by oxidative phosphorylation in ETC. (2 2H are delivered to ETC on FAD per glucose).

Question 16

Aerotolerant anaerobes

Answer 16

can live in the presence of O2, but cannot use O2 as the terminal acceptor. Make more than 2, but less than 38 ATPs per glucose

Question 17

Facultative anaerobes

Answer 17

will use O2 when it is present and make the full complement of 38 ATPs per glucose. When O2 is not available they will switch to anaerobic respiration utilizing another inorganic hydrogen/electron acceptor. Under these conditions they can make more than 2, but less than 38 ATPs per glucose.

Question 18

Obligate anaerobes

Answer 18

O2 is toxic. They do not use or survive in the presence of O2. Other inorganic hydrogen/electron acceptors are used. Make more than 2, but less than 38 ATPs per
glucose.

Question 19

examples of macromolecular polymers

Answer 19

polysaccharides, lipids, proteins and DNA

Question 20

macromolecular polymers can

Answer 20

They can all be entered into the metabolic pathways and be catabolized to generate ATP. Breakdown units from these polymers, enter glycolysis or the Krebs cycle at various points.

Question 21

proteins are broken down into

Answer 21

amino acids. The amino acids go through a

process known as deamination (lose their amino group) prior to entering the energy pathways.

Question 22

Lipids are broken down into

Answer 22

glycerol and fatty acids before these substances can be entered.

Question 23

Two types of nucleic acids

Answer 23

DNA (Deoxyribonucleic acid) and RNA (Ribonucleic acid).

Question 24

Nucleic acids are made up of

Answer 24

repeating subunits known as nucleotides

Question 25

Each nucleotide consists of

Answer 25

1 of 4 nitrogenous bases, a 5C sugar and a phosphate group

Question 26

purines

Answer 26

Adenine and guanine

Question 27

pyrimidines

Answer 27

cytosine, thymine and uracil

Question 28

DNA nucleotide

Answer 28

A. Nitrogenous bases (1 per nucleotide)
1. Adenine
2. Guanine
3. Cytosine
4. Thymine
B. 5C sugar is deoxyribose
C. Phosphate group

Question 29

RNA nucleotide

Answer 29

A. Nitrogenous bases (1 per nucleotide)
1. Adenine
2. Guanine
3. Cytosine
4. Uracil
B. 5C sugar is ribose
C. Phosphate group