Lipids (Section 2)

Question 1

Since lipids are not water soluble, so how are they digested?

Answer 1

They are first emulsified (forming new micelles) by bile acids before being digested.

Question 2

What are 3 enzymes for lipid digestion?

Answer 2

Lipase
Phospholipases
Cholesterol Esterase

Question 3

Lipase breaks down TG’s into what?

Answer 3

2,3 Diglycerides, then 2 Monoglycerides, and Free Fatty Acids

Question 4

Phospholipase digests lipids how?

Answer 4

Removes Fatty Acids from sn-2 position

Question 5

Cholesterol Esterase digests lipids how?

Answer 5

Removes Fatty Acids from cholesterol esters

Question 6

Micelles form with the aid of?

Answer 6

Bile Salts
(hydrophobic ends inward)
(hydrophilic ends outward)

Question 7

Lipid is transported from micelles into _____ during absorption?

Answer 7

Enterocytes

Question 8

Bile Salts recirculate to where?

Answer 8

Liver

Question 9

Triglycerides are resynthesized from what?

Answer 9

LCFA’s & MG

Question 10

In absorption, SCFA & MCFA go directly where & combine with what?

Answer 10

> Portal Circulation & combine with albumin

Question 11

Chylomicron’s are secreted into lymphatic circulation vs. portal circulation because?

Answer 11

b/c of it’s size. It is very large.

Question 12

FFA can be transported in the blood bound to ______ mainly through water soluble complexes called _______?

Answer 12

Albumin
Lipoproteins

Question 13

Lipoproteins stabilize themselves in what kind of environments?

Answer 13

Aqueous

Question 14

Lipoproteins specific physiological actions are?

Answer 14

Receptor Recognition
Enzyme Activation

Question 15

What is the only exogenous lipoprotein?

Answer 15

Chylomicron

(built from fat & lipids consumed from outside the body)

Question 16

TG’s are rapidly hydrolyzed from Chylomicron’s into FFA & MG’s by what enzymes?

Answer 16

Lipoprotein Lipase (LPL)
Apo C-II

Question 17

FFA’s & MG’s hydrolyzed from Chylomicron’s are absorbed where?

Answer 17

Tissue Cells
Muscle: Energy or TG Synthesis
Adipose: TG Synthesis

Question 18

The Chylomicron remnant is rich in what & is sent where for what?

Answer 18

Rich in Cholesterol

Sent to the Liver for removal

Question 19

VLDL is an ______ lipoprotein?

Answer 19

Endogenous
(already inside the body)

Question 20

VLDL is the product of other lipid sources + chylomicron remnant being packaged together where?

Answer 20

Liver

Question 21

What enzymes act on VLDL?

Answer 21

Lipoprotein Lipase (LPL)
Apo C-II

Question 22

What is formed from VLDL?

Answer 22

Intermediate Density Lipoprotein (IDL)

& Eventually…

LDL

Question 23

What enzymes act on LDL?

Answer 23

Apo B-100 receptor

Question 24

LDL deposits cholesterol where?

Answer 24

Liver & Peripheral Cells

Question 25

LDL can potentially be _____ due to it's depositing of cholesterol?

Answer 25

Atherogenic (can cause CV disease)

Question 26

LP(a) ("little a") is determined in people by what?

Answer 26

Genetics, some have high #'s, some have low #'s.

Question 27

HDL is considered the _____ cholesterol and why?

Answer 27

Good Cholesterol "vacuum cleaner of the cholesterol in our body, delivering cholesterol cells back to the liver"

Question 28

What enzyme acts on HDL?

Answer 28

Lecithin "L-CAT"

Question 29

With LDL deposits formed, smooth muscles will multiply due to what?

Answer 29

Perceived threat of invasion (immune response)

Question 30

In the immune response to LDL deposits, monocytes invade to form what?

Answer 30

Macrophages

Question 31

When unsaturated FA's within LDL is oxidized, what is an unwanted byproduct?

Answer 31

Free Radicals

Question 32

Tans Fatty Acids Increase ______ & Decrease ______ ?

Answer 32

Increase LDL Decrease HDL