Metabolism, Nutrition, and Energetics

Question 1

Subtrates

Answer 1

Substances acted on by an enzyme

Question 2

Metabolism

Answer 2

Sum of all chemical and physical changes that occur in body tissues

Question 3

Catabolism

Answer 3

Catabolic reactions

Convert large molecules into smaller ones

Question 4

Anabolism

Answer 4

Anabolic reactions

Convert small molecules into larger ones

Question 5

Nutrient pool

Answer 5

All the available nutrient molecules distributed in the blood

Question 6

Catabolism of fats

Answer 6

Lipolysis

Fats > fatty acids and glycerol

Question 7

Catabolism of carbohydrates

Answer 7

Glycogenolysis

Carbohydrates > glucose

Question 8

Catabolism of proteins

Answer 8

Proteins > amino acids

Question 9

What provides the energy for anabolism?

Answer 9

ATP from mitochondria

Question 10

4 reasons cells synthesise new organic compounds

Answer 10

1. Carry out structural maintenance or repairs
2. To support growth
3. To produce secretions
4. To store nutrient reserves

Question 11

Energetics

Answer 11

Flow of energy and its transformation from one form to another

Question 12

Oxidation

Answer 12

Loss of electrons

Decrease in potential energy

Question 13

Reduction

Answer 13

Gain of electrons

Increase in potential energy

Question 14

Coenzyme

Answer 14

Acts as an intermediary that accepts electrons from one molecule and transfers them to another molecule e.g. NAD and FAD

Question 15

Cellular respiration

Answer 15

glucose + 6 oxygen -> 6 carbon dioxide and 6 water

Question 16

Glycolysis

Answer 16

The cell gains a net 2 molecules of ATP for each glucose molecule broken down anaerobically to 2 molecules of pyruvate. 2 molecules of NADH are also produced. In most cells, electrons are passed from NADH to FAD by an intermediate electron carrier in the intermembrane space, producing FADH2, and then to the electron transport chain

Question 17

Citric acid cycle

Answer 17

Each of the two revolutions of the citric acid cycle required to break down the 2 pyruvate molecules completely yields 1 molecule of ATP by way of GTP. This cycling provides an additional gain of 2 molecules of ATP. This cycle transfers hydrogen atoms to NADH and FADH2. These coenzymes provide electrons to the electron transport chain

Question 18

Electron transport chain

Answer 18

For each molecule of glucose broken down, a total of 10 NADH and 2 FADH2 deliver their high-energy electrons to the electron transport chain

Each NADH yields 2.5 ATP and each FADH2 yields 1.5 ATP. The 2 FADH2 molecules from glycolysis yield 3 ATP molecules and 2 water molecules. Each of the 8 molecules of NADH from the citric acid cycle yields 2.5 molecules of ATP and 1 water molecules. Thus, the shuffling from the citric acid cycle to the ETC yields 23 molecules of ATP

Question 19

Gluconeogenesis

Answer 19

Formation of new glucose

Question 20

Glycogenesis

Answer 20

Formation of glycogen (storage form of glucose)

Question 21

Glycogenolysis

Answer 21

Breakdown of glycogen to glucose

Question 22

Glycolysis

Answer 22

Breakdown of glucose to pyruvate

Question 23

Beta-oxidation

Answer 23

Fatty acid molecules are broken down in a sequence of reactions into 2-carbon acetic acid fragments, and FAD and NAD+ are reduced

Question 24

Lipogenesis

Answer 24

Synthesis of lipids

Question 25

Essential fatty acids

Answer 25

Must be included in diet

Question 26

How do most lipids circulate the body?

Answer 26

Through the bloodstream as lipoproteins

Question 27

Why are lipids important energy reserves?

Answer 27

Because their breakdown provides large amounts of ATP

Question 28

Free fatty acids

Answer 28

Lipids that can diffuse easily across plasma membranes

Generally bound to albumin

Question 29

Lipoproteins

Answer 29

Lipid-protein complexes that contain large insoluble glycerides and cholesterol
A superficial coating of phospholipids and proteins makes the entire complex soluble

Question 30

Groups of lipoproteins

Answer 30

Produced in:

Intestines
1. Chylomicrons

Liver

2. VLDL
3. LDL
4. HDL

Question 31

Good cholesterol

Answer 31

HDL

Returning from peripheral tissues and doesn’t cause circulatory problems

Question 32

Why does exercise lower cholesterol?

Answer 32

Stimulates enzymes that move LDL from the blood into the liver and exercise increases the size of the protein particles that carry cholesterol in the bloodstream

Question 33

Transamination

Answer 33

Reversible chemical reaction that transfers the amino group of an amino acid to a keto acid

Question 34

Keto acids

Answer 34

Resemble amino acids except that the second carbon binds to an oxygen atom rather than to an amino group

Question 35

Deamination

Answer 35

The amino groups is removed an an ammonium ion is released

Liver cells are the primary site

Question 36

Amination

Answer 36

An ammonium ion is used to form an amino group that is attached to a molecule, yielding amino acid

Question 37

Nonessential amino acids

Answer 37

Body can make them on demand

Question 38

Amination

Answer 38

Adding of an amino group

Question 39

Absorptive state

Answer 39

Energy storage
Time following a meal
4 hours
Insulin primary hormone

Question 40

Postabsorptive state

Answer 40

Energy release
When nutrients aren’t being absorbed
Glucagon, epinephrine, glucocorticoids, and GH

Question 41

Nitrogen balance

Answer 41

Difference between total nitrogen you consume and the amount you excrete

Question 42

Minerals

Answer 42

Inorganic ions