Lecture 18

Question 1

About 1/3 of our energy needs comes from

Answer 1

Dietary Triglycerides

Question 2

About 80% of energy needs of mammalian ____ and ____ are met by oxidation of fatty acids.

Answer 2

Heart and Liver

Question 3

What is the advantage of fats over Polysaccharides?

Answer 3

FA carry more energy per carbon bc they are more reduced

FA carry less water along bc they are non-polar

Question 4

What is used for short term energy needs?

Answer 4

Glucose

Glycogen

Question 5

What is for long term energy needs, good storage and slow delivery?

Answer 5

Fats

Question 6

Dietary fats are absorbed in the?

Answer 6

Small Intestine

Question 7

Bile salts emulsify dietary in the

Answer 7

Small Intestine

Question 8

Intestinal Lipases degrade

Answer 8

TAG’s

Question 9

FA’s are taken up by the ____ and converted into _____.

Answer 9

Intestinal mucosa

TAG’s

Question 10

TAGS are incorporated with cholesterol and apolipoproteins, into

Answer 10

chylomicrons

Question 11

Chylomicrons move through the lymphatic system and

Answer 11

bloodstream to tissue

Question 12

Lipoprotein lipase, is activated by ___ in the and converts ___ to ____.

Answer 12

apoC
capillary
TAGS FA/Glycerol

Question 13

Lipids are transported in the blood as

Answer 13

chylomicrons

Question 14

Hydrolysis of fats yields ___ and is catalyzed by ___.

Answer 14

FA & glycerol

Lipases

Question 15

Some lipases are regulated by

Answer 15

Glucagon & Epinephrine

Question 16

Which hormone means “We are out of glucose?”

Answer 16

we are out of glucose

Question 17

Hormones trigger mobilization of stored ____.

Answer 17

TAG’s

Question 18

Which enzyme activates glycerol at the expense of ATP?

Answer 18

Glycerol Kinase

Question 19

Glycerol —> L-Glycerol 3-Phosphate

Answer 19

Glycerol Kinase

via Phosphorylation

Question 20

L- Glycerol 3-phosphate —> Dihydroxyacetone Phosphate

Answer 20

Glycerol 3-phosphate dehydrogenase

Question 21

DHAP —> D- Glyceraldehyde 3-phosphate

Answer 21

Triose phosphate isomerase

Question 22

Fatty acids are converted into

Answer 22

Fatty acyl- CoA

Question 23

Fats are degraded into Fatty Acids and glycerol in the ____ of _____.

Answer 23

Cytoplasm of Adipocytes

Question 24

Fatty Acids are transported to ____ for fuel.

Answer 24

other tissues

Question 25

B-oxidation of FA's occurs in ____.

Answer 25

Mitochondria

Question 26

Small Less than __ carbons fatty acids diffuse freely across mitochondrial membranes.

Answer 26

12

Question 27

Large FA's are transported via the ____ into mitochondrial membrane.

Answer 27

Acyl- Carnitine transporter

Question 28

This shuttles FA's into the mitochondrial matrix.

Answer 28

Carnitine shuttle

Question 29

What are the 3 stages of Fatty Acid Oxidation?

Answer 29

1. Oxidative conversion of 2-carbon units into acetyl-co a via B-oxidation 2. oxidation of acetyl coa into CO2, via CAC 3. Creates ATP from NADH and FADH2, via respiratory chain

Question 30

Each pass removes 1 acetyl moiety in the form of acetyl-coa

Answer 30

B-oxidation pathway

Question 31

Which BO enzyme is most closely related to succinate DH?

Answer 31

Acyl-CoA DH

Question 32

Palmitoyl CoA ---> Trans Enoyl CoA

Answer 32

Acyl CoA DH

Question 33

Which enzymes catalyzes the dehydrogenation of an alkane to an alkene?

Answer 33

Acyl CoA DH

Question 34

What enzyme catalyzed hydration of an alkene?

Answer 34

Enoyl CoA hydratase

Question 35

Trans enoyl-Coa ---> B-hydroxy acyl-CoA

Answer 35

Enoyl-CoA hydratase

Question 36

Water adds across the double bond yielding an alcohol, which enzyme does this?

Answer 36

Enoyl-CoA Hydratase

Question 37

Analogous to fumarase reaction in CAC

Answer 37

Enoyl-CoA Hydratase

Question 38

Dehydrogenation of alcohol

Answer 38

B-hydroxyacyl-Coa DH

Question 39

Uses NAD cofactor as the hydride acceptor

Answer 39

B-hydroxyacyl-Coa DH

Question 40

Analagous to Malate DH in CAC

Answer 40

B-hydroxyacyl-Coa DH

Question 41

Transfers of Fatty Acid Chain

Answer 41

Acyl-CoA acetyltransferase (thiolase)

Question 42

Which mechanism does thiolase us?

Answer 42

Covalent Mechanism

Question 43

Thiolase is also known as

Answer 43

Acyl-CoA acetyltransferase

Question 44

Also known as thiolase

Answer 44

Acyl-CoA acetyltransferase

Question 45

Net reaction is thiolysis of carbon-carbon bond

Answer 45

Acyl-CoA acetyltransferase

Question 46

Carbonyl carbon in B-ketoacyl is _____.

Answer 46

electrophilic

Question 47

Active site thiolate acts an nucleophile and releases ____.

Answer 47

Acetyl-CoA

Question 48

Terminal sulfur in CoA-SH aces as an ____ and picks up the fatty acid chain from the enzyme ____.

Answer 48

nucleophile | Thiolase

Question 49

Naturally occurring Unsaturated FA contain cis double bonds

Answer 49

True

Question 50

2 add'l enzymes are required

Answer 50

1. Isomerase | 2. Reductase

Question 51

What does enoyl-CoA Isomerase do?

Answer 51

converts cis double bonds ---> trans double bonds

Question 52

In Oxidation of polyunsaturated FA, what happens differently?

Answer 52

Use an add'l NADPH and also skip the 1st step of B-oxidation

Question 53

In oxidation of odd numbered fa's, most dietary fa are ___- numbered.

Answer 53

Even-numbered

Question 54

Many plants and some marine organisms also create

Answer 54

Odd-number FA

Question 55

Proprionyl-CoA forms from B-oxidation of ___.

Answer 55

odd-numbered FA's

Question 56

Bacterial metabolism in the rumen of ruminents also produces

Answer 56

Propionyl- CoA

Question 57

Entry of Acetyl-CoA into the CAC requires ___.

Answer 57

Oxaloacetate

Question 58

When oxaloacetate is depleted, acetyl coa is converted to

Answer 58

Ketone Bodies

Question 59

What is the source of ketone bodies?

Answer 59

Liver

Question 60

During starvation, what happens to ketone bodies?

Answer 60

Production

Question 61

High levels of which 2 substrates lower blood pH ---> acidosis

Answer 61

Acetoacetate | Beta-hydroxybuturate

Question 62

Acetoacetate | Beta-hydroxybuturate both lower blood pH, are exported as an energy sources for ___.

Answer 62

Heart Skeletal Muscle Kidney Brain