Lecture 15 - Triacylglycerol Formation

Question 1

Most lipids stored in the body are….

Answer 1

triglycerides

Question 2

what is a very important precursor for forming lipids?

Answer 2

phosphatidic acid

Question 3

what are 3 important uses for cholesterol?

Answer 3

1. Essential component of the plasma membrane
2. Precursor to steroid hormones
3. Intermediates in the cholesterol metabolism pathway are precursors to other cellular products (Ubiquinone)

Question 4

Cholesterol metabolism requires…..

Answer 4

cytosolic acetyl-coA

Question 5

3 acetyl-coA molecules join to form….

Answer 5

HMG-CoA

Question 6

What is the rate-controlling enzyme in cholesterol metabolism?

Answer 6

HMG-CoA reductase

Question 7

HMG-CoA reductase is a drug target for….

Answer 7

cholesterol-lowering drugs (the statins)

Question 8

cholesterol can be _____ and packed into ____ particles

Answer 8

cholesterol can be ESTERIFIED and packaged into LIPOPROTEIN particles

Question 9

what are eicosanoids?

Answer 9

a large class of relatively short-lived molecules
(type of lipid_

Question 10

Eicosanoids are derived from…

Answer 10

fatty acid arachidonate

Question 11

What are some effects of Eicosanoids?

Answer 11

stimulate smooth muscle contraction which causes pain and clotting

Question 12

a pain killer would block the conversion of ___ to ____

Answer 12

arachidonate to an eicosanoid

Question 13

sphingolipids are utilized where in the body?

Answer 13

the nervous system

Question 14

Sphingolipids use _____ rather than ____ as a backbone

Answer 14

use serine rather than glycerol as a backbone

Question 15

What are some functions of sphingolipids?

Answer 15

cell growth
cell migration
regulation of apoptosis

Question 16

Give an example of a disease associated with sphingolipids?

Answer 16

Neiman-Pick
unable to degrade sphingolipids

Question 17

In the FED state, dietary lipid is…..

Answer 17

packaged in lipoprotein chylomicron (ultimately stored in fat cells)

Question 18

in the FED state, carbohydrates are stored as….

Answer 18

glycogen until max glycogen is formed - then carbohydrates are stored as fat

Question 19

what is the major hormone involved while in the fed state?

Answer 19

insulin

Question 20

what does insulin do while in the fed state?

Answer 20

stimulates fatty acid synthesis of liver and fat cells. Favors triglyceride formation

Question 21

In the fasted state, what is produced — fatty acids or triglyceride?

Answer 21

fatty acids are produced by the breakdown of triglycerides in fat cells

Question 22

what hormone stimulates the breakdown of triglyceride to fatty acids?

Answer 22

epinephrine

Question 23

In the fasted state, the liver takes up….

Answer 23

fatty acids

Question 24

in the fasted state, the liver takes up fatty acids and does what with them?

Answer 24

oxidizes them to carbon dioxide or partially oxidizes them to ketone bodies

Question 25

What is the role of fat cells?

Answer 25

synthesize, store, and release fat

Question 26

What is the role of muscle cells?

Answer 26

utilize fat and ketone bodies

Question 27

What is the role of the liver? (4 things)

Answer 27

fat synthesis VLDL secretion fatty acid oxidation ketone body synthesis

Question 27

What is the role of the liver? (4 things)

Answer 27

fat synthesis VLDL secretion fatty acid oxidation ketone body synthesis

Question 28

during feeding, what hormone becomes elevated?

Answer 28

insulin

Question 29

Glycogen is converted to _____ triglycerides converted to _______

Answer 29

glycogen converted to HEXOPHOSPHATE SUGAR Triglycerides converted to FATTY ACIDS

Question 30

While fatty acid oxidation and ketone body formation are high, Molonyl-CoA levels are ______

Answer 30

high

Question 31

Malonyl-coA is a rate determining intermediate in.....

Answer 31

fatty acid synthesis

Question 32

When malonyl-CoA levels are low, what happens?

Answer 32

-the inhibition of fatty acid oxidation is lifted (so overall increased) -Increased ketone body formation

Question 33

in the fasted state, what 2 hormones become elevated?

Answer 33

glucagon and epinephrine

Question 34

In the fasted state, Malonyl-CoA levels are______

Answer 34

LOW

Question 35

In the fasted state, epinephrine concentration in the blood is elevated. What does this cause?

Answer 35

Stimulated fat cells to release more fatty acids to the blood stimulates the liver to produce ketone bodies

Question 36

What body part primarily uses glucose?

Answer 36

the brain

Question 37

Gluconeogenesis becomes critical in the ___ state

Answer 37

fasted

Question 38

If starvation continues, what will be broken down?

Answer 38

amino acids (not preferred)

Question 39

During exercise, what can you say about blood flow?

Answer 39

blood flow is shunted away from most tissues except for the MUSCLES and the BRAIN

Question 40

Name 3 things that occur biochemically during anaerobic exercise

Answer 40

-Muscle breaks down its glycogen stores -glycogen phosphorylase is activated (causes glycogen to breakdown quicker) -NO EFFECT ON LIPID METABOLISM

Question 41

The anaerobic state involves what kind of exercise?

Answer 41

intense exercise. Quick, small amounts of ATP are produced

Question 42

Name 3 things that happen biochemically during AEROBIC exercise

Answer 42

-increased epinephrine leads to fat cells releasing fatty acids -fatty acids are then oxidized by muscle cells -Malonyl-CoA concentration is lowered by AMP kinase activity and increased AMP concentration

Question 43

Which is more severe --- Type 1 or Type 2 diabetes

Answer 43

type 1 is more severe

Question 44

explain why type 1 diabetes develops

Answer 44

pancreatic beta cells are impaired. Causes insufficient release of insulin (ALMOST NO INSULIN PRODUCTION)

Question 45

Explain type 2 diabetes

Answer 45

type 2 diabetes can lead to abnormally high levels of insulin because the body becomes insensitive to insulin. More insulin is needed to have the same effects

Question 46

explain 3 things that occur in type 1 diabetes that makes it so severe

Answer 46

-fatty acids are released from fat cells -Ketone body levels are elevated (which can create strong osmotic pressure_ -Gluconeogenesis is increased

Question 47

What is the treatment for type 1 diabetes?

Answer 47

Insulin is given

Question 48

What is the treatment for type 2 diabetes?

Answer 48

metformin is given -inhibits gluconeogenesis and activates muscle glucose uptake by the stimulation of AMP kinase

Question 49

What is a good treatment for both Type 1 and Type 2 diabetes?

Answer 49

EXERCISE - most likely to stimulate AMP kinase