lecture 17- energy balance and metabolism I

Question 1

what is the feta G sub not in the body

Answer 1

-12000 cal/mole

Question 2

what is the final common pathway for the transport of almost all the carbs to the tissue cells

Answer 2

glucose

Question 3

what can galactose and glucose be converted into in order to enter the glycolytic pathway

Answer 3

fructose-6-phosphate

Question 4

where can phosphorylation of glucose be reversed

Answer 4

liver, renal and intestinal cells

Question 5

what does glucokinase do

Answer 5

transfers phosphate from ATP

Question 6

what does phosphatase do

Answer 6

removes phosphate

Question 7

what does phosphorylase

Answer 7

catalyzes production of glucose-1-phosphate from glycogen

Question 8

what factors can activate phosphorylase

Answer 8

epinephrine and glucagon

Question 9

what are the effects of phosphorylase

Answer 9

promotes conversion of glycogen to glucose (then glucose can be released into blood)

Question 10

what are the end products of glycolysis

Answer 10

pyruvic acid (2), hydrogens (4), ATP (2 molecules)

Question 11

what are the end product of the conversion from pyretic acid to acetyl-CoA

Answer 11

acetyl CoA (2), hydrogens (4), CO2 (2)

Question 12

where does the TCA cycle occur

Answer 12

mitochondrial matrix

Question 13

what are the end products of the TCA cycle

Answer 13

hydrogens (16), ATP (2), CO2 (4)

Question 14

where does oxidative phosphorylation

Answer 14

occurs on mitochondrial cristae

Question 15

what are the fate of electrons removed from hydrogen ions

Answer 15

enter ETC

Question 16

what are the major components of the ETC

Answer 16

flavoprotein, several iron sulfide proteins, ubiquinone, cytochrome A3 (cytochrome oxidase)

Question 17

where is cytochrome A3 (cytochrome oxidase) located

Answer 17

inner membrane

Question 18

what are the numbers of ATPs formed per glucose molecule (oxidative phosphorylation)

Answer 18

2 ATPs from glycolysis, 2 ATPs from TCA, 34 ATPs from oxidative phosphorylation

Question 19

what is the maximum number of ATPs per glucose molecule

Answer 19

38

Question 20

how many calories are there per mole of glucose

Answer 20

456,000

Question 21

what is glucose preferentially stored as until the storage cells(liver and muscle) are saturated

Answer 21

glycogen

Question 22

how is triglyceride absorbed form intestinal lumen

Answer 22

most are digested into monoglycerides and fatty acids,
intestinal epithelial cells resynthesize these into triglycerides that enter the lymph as chylomicrons,
apoprotein B is absorbed to the chylomicron surfaces

Question 23

how are chylomicrons transported to the venous system

Answer 23

via thoracic duct

Question 24

what tissues are especially involved in removing chylomicrons form the blood

Answer 24

adipose tissue, skeletal muscle, heart

Question 25

where is lipoprotein lipase transported and what does it doe

Answer 25

transported to surface of capillary epithelial cells in order to hydrolyze chylomicron triglycerides, releasing fatty acids and glycerol

Question 26

what conditions increase the utilization of fat for energy

Answer 26

starvation, diabetes mellitus

Question 27

what type of lipoproteins are synthesized by intestinal cells

Answer 27

chylomicrons

Question 28

describe VLDLs

Answer 28

high concentrations of triglycerides and moderate amounts of cholesterol and phospholipids. transport lipids mainly from liver to adipose tissue

Question 29

describe LDLs

Answer 29

high concentration of cholesterol and moderate concentrate of phospholipids

Question 30

describe HDLs

Answer 30

high concentrations of proteins and low concentrations of cholesterol and fatty acids

Question 31

what cells do not use fatty acids for energy

Answer 31

brain cells and RBCs

Question 32

where are fatty acids converted to acetyl-CoA

Answer 32

in mitochondria

Question 33

how does acetyl-CoA enter the TCA cycle

Answer 33

binding to oxaloacetic acid

Question 34

what are the products from beta-oxidation of one molecule of stearic acid

Answer 34

9 acetyl-CoA molecules and 146 molecules of ATP

Question 35

what type of acid is acetoacetic acid

Answer 35

keto acid

Question 36

give examples of ketone bodies

Answer 36

acetoacetic acid, beta-hydroxybutyric acid, and acetone

Question 37

what conditions favor ketosis

Answer 37

starvation, diabetes, diet composed almost entirely of fats

Question 38

what are involved in the 2 set process of the synthesis of fatty acids

Answer 38

malonyl-CoA and NADPH

Question 39

what is the importance of fat synthesis

Answer 39

more fat can be stored in tissues than carbs. | weight for weight, fat contains 2.5X the energy of carbs

Question 40

what occurs as the result of damage to the vascular endothelium

Answer 40

increases the expression of adhesion molecules, | decreases release of NO and other substances that prevent adhesion of macromolecules and cells

Question 41

what is the role of macrophages in the development of atherosclerotic plaques

Answer 41

ingest lipoproteins, become foam cells, form visible fatty streaks

Question 42

what are the basic causes of atherosclerosis

Answer 42

increased LDLs and familial hypercholesterolemia (defective LDL receptors)