Class 4&5 - Metabolism & Nutrition

Question 1

A typical cell has about ___ ATP molecules

Answer 1

1 million

Question 2

A molecule of ATP lasts about __ before being used

Answer 2

1 minute

Question 3

__% of energy released in catabolism is used for cellular functions, the rest is converted into heat to maintain the body’s temperature

Answer 3

40%

Question 4

Oxidation reactions involve the ___ of ___ from an atom, which _____ its potential energy.

Answer 4

REMOVAL, ELECTRONS, DECREASES

Question 5

Redox reactions involve the ____ of ____ to a molecule which ____ its potential energy

Answer 5

ADDITION, ELECTRONS, INCREASES

Question 6

What are the two biological coenzymes in the human body? What are they derivates of?

Answer 6

NAD+ (niacin)

FAD (riboflavin)

Question 7

Oxidation reactions usually involve loss of ___ atoms. Reduction reactions usually involve gaining these atoms.

Answer 7

Hydrogen

Question 8

What is phosphorylation?

Answer 8

addition of a phosphate group to a molecule

Question 9

What is substrate-level phosphorylation?

Answer 9

when a phosphate group is transferred to ADP directly from a substrate (Kreb’s cycle)

Question 10

Substrate-level phosphorylation occurs in the…

Answer 10

cytosol

Question 11

Oxidative phosphorylation occurs in the…

Answer 11

mitochondria

Question 12

What is oxidative phosphorylation?

Answer 12

when electrons are liberated from electron donors to electron acceptors (such as oxygen, like in the ETC)

Question 13

Oxidation = removal of electrons from an atom. Oxidative phosphorylation means these electrons are then transferred to electron acceptors (reduction), which then power ATP synthesis.

Answer 13

good job

Question 14

Oxidation is usually an _____ reaction

Answer 14

exergonic

Question 15

A highly reduced compound has many ___ atoms

Answer 15

hydrogen

Question 16

a lower energy, oxidized compound has many ____ atoms

Answer 16

oxygen

Question 17

Oxidation of glucose means that…

Answer 17

hydrogen atoms are removed (electrons removed/released)

Question 18

How does the addition of a phosphate group to a molecule affect its potential energy?

Answer 18

increases it (release of the phosphate group will release energy) - it’s temporary energy storage

Question 19

Transferring a high energy phosphate group directly to ADP is an example of…

Answer 19

substrate-level phosphorylation

Question 20

Carbs represent what percentage of the body’s weight?

Answer 20

2-3%

Question 21

Hydrolytic enzymes in the S.I. break carbs down into what simple sugars?

Answer 21

glucose
fructose
galactose

Question 22

Glucose constitutes about __% of the simple sugars absorbed in the intestines

Answer 22

80%

Question 23

The only sugar normally found in blood is..

Answer 23

glucose

Question 24

Glucose may follow 1 of 4 paths in the body:

Answer 24

ATP production
amino acid synthesis
glycogen synthesis/glycogenesis
triglyceride synthesis

Question 25

What happens when glucose is phosphorylated? Does this use or create ATP?

Answer 25

it becomes glucose-6-phosphate uses ATP

Question 26

The liver can store about ___ of glycogen. Skeletal mm can store about ____.

Answer 26

125g (liver) 375 (skeletal mm)

Question 27

Once the glycogen storage capacity is reached in the body, what happens to excess glucose?

Answer 27

triglyceride synthesis --> stored in adipose tissue

Question 28

Glucose enters intestinal cells for absorption via ____, but the rest of the body's cells via _____.

Answer 28

secondary active transport (requires ATP) facilitated diffusion (does not require ATP)

Question 29

What method of secondary active transport does glucose enter body cells via?

Answer 29

Na+/glucose symporters

Question 30

How is insulin able to increase uptake of glucose into cells?

Answer 30

stimulates insertion of GluT transporters into the cell membrane

Question 31

Insulin is NOT required for glucose uptake in what types for cells?

Answer 31

actively working skeletal mm cells

Question 32

Glucose entry is ALWAYS on/active/possible in what two types of cells?

Answer 32

hepatocytes and neurons

Question 33

Only ____ contain the enzymes to convert G6P back into glucose

Answer 33

hepatocytes

Question 34

The process of glycolysis oxidizes one glucose molecule to produce what 6 molecules?

Answer 34

2 pyruvic acid 2 ATP (well it produces 4 but consumes 2) 2 NADH + H+

Question 35

If oxygen is scarce after glycolysis, pyruvic acid will be reduced to form ____, which also allows for regeneration of _____

Answer 35

lactic acid NAD+

Question 36

How do 2 pyruvic acid + 2 NAD H + H+ become 2 lactic acid + 2 NAD+?

Answer 36

Each pyruvic acid molecule gains 2 H+ molecules (4 H+) to create 2 lactic acid + 2 NAD+

Question 37

If conditions are aerobic, pyruvic acid will enter ____ via a _______

Answer 37

mitochondria via a transporter protein

Question 38

Within the mitochondria, pyruvic acid is converted into _______

Answer 38

acetyl coenzyme A

Question 39

Where does the Krebs cycle occur?

Answer 39

matrix of the mitochondria

Question 40

The Krebs cycle starts with ____ and ends with ____

Answer 40

citric acid oxalecetic acid

Question 41

For each turn of the Krebs cycle, how much ATP is produced?

Answer 41

1

Question 42

What is the most important outcome of the Krebs cycle?

Answer 42

Formation of NADH and FADH2, which will later yield many more ATP from the ETC

Question 43

How much CO2 is liberated from the Krebs cycle?

Answer 43

6 molecules

Question 44

How does the ETC work?

Answer 44

it's a series of integral proteins in the very folded inner membrane of the mitochondria that function as electron carriers -> each carrier is oxidized or reduced as it picks up or gives up electrons. As electrons pass through, energy is released and ATP is formed.

Question 45

What is the final ETC electron acceptor?

Answer 45

oxygen

Question 46

For every molecule of NADH + H+, how many ATP are generated? | For every molecule of FADH2, how many ATP are generated?

Answer 46

NADH + H+ = 2-3 ATP FADH2 = 1-2 ATP

Question 47

Cellular respiration will generate either __ or __ ATP molecules per molecule of glucose catabolized

Answer 47

30-32

Question 48

The final result of cellular respiration is:

Answer 48

6 CO2 + 6 H2O + 30-32 ATP

Question 49

Glycogenesis in the liver and skeletal muscle is stimulated by ____

Answer 49

insulin

Question 50

Glycogenolysis splits up glycogen into G6P via ____ which is stimulated by either ___ or ____.

Answer 50

via phosphorylation glucagon & NE

Question 51

Lactic acid generated in muscle cells from glycolysis can be converted back into glucose by....

Answer 51

the liver

Question 52

Gluconeogenesis is the generation of new glucose from _____

Answer 52

non-carb sources

Question 53

What 3 non-carb molecules in the body can be converted into glucose?

Answer 53

amino acids (60% of them) lactic acid glycerol

Question 54

Amino acids and lactic acid can be converted into...

Answer 54

pyruvic acid

Question 55

What hormones stimulate gluconeogenesis?

Answer 55

cortisol and glucagon

Question 56

True or false: thyroid hormones can mobilize proteins or triglycerides to make them available for gluconeogenesis

Answer 56

true

Question 57

True or false: fatty acids can be converted directly into glucose

Answer 57

false