Metabolism Overview

Question 1

Define Catabolism

Answer 1

The breakdown of large molecules, commonly involving oxidative reactions (Exothermic, releases ATP via respiratory chain)

Question 2

Define Anabolism

Answer 2

Synthesis of large, complex compounds from smaller precursors (Endothermic, requires ATP // Amino acids, protein, carbohydrates, triacylglycerol // glycogen)

Question 3

Define Amphibolic

Answer 3

Participates in anabolic and catabolic functions (Citric Acid Cycle)

Question 4

States where normal metabolism allows for adaptation

Answer 4

Fed, Fasting, Starving, Exercising, Pregnancy, Lactating

Question 5

The ____ is the source of glucose

Answer 5

Intestine

Question 6

In the fed state, ____ stimulates ____ uptake by cells

Answer 6

Insulin; glucose

Question 7

Glucose uptake by the liver is _______

Answer 7

Independent of insulin

Question 8

Insulin is made in the ____ and controls _____ and uptake during the ____

Answer 8

Endocrine pancreas; glucose oxidation ; fed state

Question 9

Excess glucose is stored in the muscle as

Answer 9

Glycogen

Question 10

During the fed state brain glucose uptake is unaltered (T or F)

Answer 10

TRUE

Question 11

During the fed state, lipolysis is….

Answer 11

Suppressed

Question 12

Increased during the the fed state

Answer 12

Muscle/Adipose Glucose intake and protein synthesis

Question 13

Decreased during the fed state

Answer 13

Muscle fatty acid uptake, insulin secretion

Question 14

_____ is the source of glucose and glucose production is taken up by the ____

Answer 14

Liver; brain

Question 15

Prolonged fasting depleted glycogen reserves and ______ arising from net muscle protein breakdown

Answer 15

Amino acids

Question 16

______ from hydrolysis of stored muscle glycogen provides carbons to support ______

Answer 16

Lactate; gluconeogenesis

Question 17

Adipose releases _____ that are used by liver and skeletal muscle

Answer 17

free fatty acids

Question 18

Ketones are ______

Answer 18

Partially oxidized fatty acids

Question 19

glucose transporter of muscle + adipose tissue in intracellular vesicles

Answer 19

GLUT-4

Question 20

Increased in the fasting state

Answer 20

Plasma non-esterified fatty acids, plasma concentration of ketone bodies

Question 21

Decreased in fasting state

Answer 21

Muscle fatty acid uptake, insulin secretion

Question 22

Alternative fuel size during prolonged fasting/starvation

Answer 22

Ketones

Question 23

During starvation, ____ is used to supply amino acids for ______ and oxidized in skeletal muscle

Answer 23

protein; gluconeogenesis

Question 24

Substrates during starvation are oxidized by the _____ to support energy demands and contribute to _____ synthesis

Answer 24

Liver ; ketone body

Question 25

Adipose tissue reserves are depleted during ____

Answer 25

prolonged starvation

Question 26

Main substrates during prolonged starvation

Answer 26

glucose, amino acids, ketone bodies

Question 27

States of abnormal metabolism

Answer 27

Nutritional deficiency

Caloric excess

Enzyme deficiency or inappropriate regulation

Abnormal secretion of hormones

Actions of drugs and toxins

Question 28

Macronutrient Metabolic Fuel %

Answer 28

Carbohydrate = 40-60%
Lipid = 30-40%
Protein = 10-15%

Question 29

Carbohydrate Metabolic Pathways

Answer 29

Glycolysis, Citric Acid Cycle, Glycogenesis, Pentose Phosphate Pathway, Glycogenolysis, Gluconeogenesis

Question 30

Lipid Metabolic Pathways

Answer 30

Lipolysis, B-Oxidation, Citric Acid Cycle, Lipogenesis, Ketogenesis, Cholesterol & Steroid Synthesis, Esterification

Question 31

Protein Metabolic Pathways

Answer 31

Nonprotein Derivative Synthesis, Protein/A.A. Synthesis, Transamination & Deamination, Ketogenesis, Citric Acid Cycle, Gluconeogenesis, Urea Synthesis

Question 32

Two levels of organization of metabolic pathways

Answer 32

Tissue/Organ Level

Subcellular Level

Question 33

Tissue/Organ Level

Answer 33

Substrates entering or metabolite exiting tissues/organs

Question 34

Subcellular Level

Answer 34

Each organelle or compartment has specific roles in metabolic pathways

Question 35

Four metabolic pathways that take place in the liver

Answer 35

Gluconeogenesis, Plasma Protein Synthesis, Lipogenesis, Ketogenesis

Question 36

Pathways that take place in the Mitochondria

Answer 36

Kreb’s/TCA Cycle, B-Oxidation, Gluconeogenesis (and cytosol)

Question 37

Pathways that take place in the Cytosol

Answer 37

Pentose Phosphate Pathway, FA Synthesis, Gluconeogenesis (and mitochondria)

Question 38

Pathways that take place in the Ribsomes

Answer 38

Protein synthesis

Question 39

Mechanisms involved in regulation of metabolites through metabolic pathways

Answer 39

Nonequilibrium, Allosteric modifiers, Hormones

Question 40

Nonequilibrium Reaction Catalyst Enzymes

Answer 40

Hexokinase, phosphofructokinase, pyruvate kinase

Question 41

Allosteric Modifiers

Answer 41

Changes enzyme efficiency by modifiers/effectors (changes enzyme function)

Question 42

Allosteric Inhibitor Reaction

Answer 42

Glucose –> G6P inhibits hexokinase

Question 43

Hormones

Answer 43

Can rapidly alter activity or cellular localization of existing enzyme molecules

Or slowly changing enzyme content by altering rate of enzyme synthesis

Question 44

Strictly ketogenic amino acids

Answer 44

Lysine and Leucine

Then converted to Acetyl CoA ONLY

Question 45

____ and ____ are the hormones that control glucose oxidation and uptake

Answer 45

Insulin ; glucagon

Question 46

In the fed state, glucose from the liver goes to

Answer 46

the brain, adipose tissue, muscle

Question 47

In the fed state, FFAs from adipose tissue goes to

Answer 47

The liver and muscle tissue

Question 48

In the fasting/starvation state, _____ is made in the endocrine pancreas

Answer 48

Glucagon

Question 49

The products of digestion when completely oxidized become ____

Answer 49

Acetyl CoA, which is then oxidized by the CAC