M1-C1-L79 --> Lipoproteins I

Front 1

What does albumin do?

Back 1

Serum albumin aids in the transport of water insoluble molecules in the blood.

Front 2

Where is albumin made?

Back 2

Liver

Front 3

How do you coagulate albumin from blood?

Back 3

Heat

Front 4

What do lipoproteins do?

Back 4

Aid in transport of Phospholipids, Cholesterol, and Triglycerides.

Front 5

Where are lipoproteins made?

Back 5

In the liver and intestines.

Front 6

What would you expect to see in the core of the lipoprotein?

Back 6

Nonpolar lipids (e.g. - triglycerides and cholesteryl esters)

Front 7

What would you expect to see in the surface MONOLAYER of the lipoprotein?

Back 7

Polar lipids (e.g. - phosphoplipids, FREE cholesterol) and apolipoproteins

Front 8

What is the protein component of a lipoprotein called and describe its orientation in the lipoprotein.

Back 8

Apolipoprotein.

Wraps around ball of fat.

Front 9

What are the faces of the apoprotein and what do they face?

Back 9

Nonpolar face - faces the interior side of the lipoprotein complex

Polar face - faces the plasma

Front 10

How do apoproteins serve the association of lipoprotiens and cellular lipoprotein receptor?

Back 10

They serve as ligands to the receptor

Front 11

Apoproteins can also do what with some enzymes?

Back 11

Can activate enzymes involved in lipid metabolism/transfer.

Front 12

What are chylomicrons?

Back 12

Lipoproteins made by the intestines that helps transport exogenous lipids.

Front 13

What are the classification of lipoproteins?

Back 13

Chylomicron
VLDL - Very Low Density Lipoprotien
IDL - Intermediate Density Lipoprotein
LDL - Low Density Lipoprotein
HDL - High Density Lipoprotein

Front 14

Lipoproteins are proportional to what?

Back 14

Inversely proportional to diameter. Thus HDL has less lipids than VLDL. Chylomicrons have the most lipids to them.

Front 15

Which lipoproteins are considered alpha (or A) lipoproteins?

Back 15

Chylomicron and HDL

Front 16

Which lipoproteins are considered beta (or B) lipoproteins?

Back 16

LDL, IDL, VLDL

Front 17

Which lipoprotein is important for transporting exogenous lipids?

Back 17

Chylomicrons

Front 18

Which lipoprotein is important for transporting endogenous lipids?

Back 18

LDL, IDL, and VLDL

Front 19

What is the function of HDL?

Back 19

1. Recycles cholesterol back to liver
2. Supplies Apo C-II proteins to lipoproteins
3. Supplies Apo E proteins to lipoproteins

Front 20

Rank the lipoproteins in decreasing triglyceride:cholesterol ratio.

Back 20

1. Chylomicrons (highest ratio)
2. VLDL
3. IDL
4. LDL
5. HDL (smallest ratio)

Front 21

Rank lipoproteins based on decreasing protein:lipid ratio.

Back 21

1. HDL (highest ratio)
2. LDL
3. IDL
4. VLDL
5. Chylomicrons

Front 22

Rank the lipoproteins based on decreasing density.

Back 22

1. HDL (highest ratio)
2. LDL
3. IDL
4. VLDL
5. Chylomicrons

Front 23

Exogenous lipids found in the vascular system come from where?

Back 23

Intestines

Front 24

Endogenous lipids found in the vascular system come from where?

Back 24

Liver

Front 25

What are the three functions of apoproteins in lipoproteins?

Back 25

1. Structual integrity
2. Mediate cellular uptake
3. Plasma Enzyme activators for lipid metabolism

Front 26

Lipoproteins are delivered to the vascular system by what process?

Back 26

Exocytosis

Front 27

A chylomicron is composed of what?

Back 27

1. B-48 Apoprotein
2. Phospholipids
3. Cholesterol
4. Triglycerides

Front 28

A VLDL is composed of what?

Back 28

1. B-100 Apoprotein
2. Phopholipids
3. Cholesterol
4. Triglycerides

Front 29

Nascent lipoproteins acquire what from HDL?

Back 29

1. CII Apoprotein (regulatory subunits)
2. E Apoprotein (regulatory subunits)

Front 30

What organ takes care of remnant lipoproteins and through what mechanism?

Back 30

Liver
Receptor mediated endocytosis

Front 31

Delivery of fatty acid in to cells require what enzyme?

Back 31

LPL - Lipoprotein Lipase

Front 32

What activates LPL?

Back 32

Apo C-II

Front 33

LPL is secreted from where?

Back 33

Muscle and adipose cells

Front 34

LPL hydrolyzes what in to what?

Back 34

Triglycerides into FFA and glycerol

Front 35

What happens to the glycerol after LPL hydrolyzes it out of triglycerides?

Back 35

Diffuses out of adipose/muscle cell where it is diffused to the liver and converted to G6P

Front 36

What two things must happen to a chylomicron to become a chylomicron remnant?

Back 36

1. LPL hydrolyzes the fat out of it.
2. Apo C-II and Apo E are returned to HDL

Front 37

How does Apo C II serve chylomicrons?

Back 37

They inhibit uptake by liver cells. Thus chylomicrons with lots of Apo C are rich with triglycerides.

Front 38

Chylomicron remnant receptors are also known as what?

Back 38

LRP (LDL-related Receptor Proteins)

Front 39

What genes are responsible for making B-100 and B-52?

Back 39

The same damn one, but in order to make B-52, additional mRNA editing is done to create an early stop codon.

Front 40

What is the Triglyceride:Cholesterol ratio in cylomicrons?

Back 40

10:1

Front 41

What is the Triglyceride:Cholesterol ratio in cylomicrons remnants?

Back 41

1:1

Front 42

What is the Triglyceride:Cholesterol ratio in VLDL?

Back 42

5:1

Front 43

What is the Triglyceride:Cholesterol ratio in IDL?

Back 43

1:1

Front 44

What must occur for VLDL to become IDL?

Back 44

1. Release of triglycerides via LPL.
2. Apo C-II and Apo E are returned to HDL

Front 45

What is the Triglyceride:Cholesterol ratio in IDL?

Back 45

1:5

Front 46

What must happen for IDL to become LDL?

Back 46

1. Loss of triglycerides (via LPL or hepatic triacyl glycerol lipase)
2. Transfer of Apo E to HDL

Front 47

T/F - Apo C II can be found on IDL?

Back 47

False, so the activity of LPL is lower in IDL than VLDL

Front 48

IDL particles are disposed of how and by what?

Back 48

Liver takes 2/3's of them and recycles them into LDL.

Front 49

Most of the cholesterol in the blood is found as what form of lipoprotein?

Back 49

LDL

Front 50

Apo E is crucial for what two things?

Back 50

1. Removal of IDL's
2. Conversion of IDL's to LDL's.

Front 51

LDL receptors recognize what protein ligands on LDL's?

Back 51

Apo B-100
Apo E

Front 52

What are the slowest lipoproteins to be cleared from plasma and why?

Back 52

IDL and LDL (slowest) due to low amounts of Apo E

Front 53

What is the benefit of slow clearance?

Back 53

Allows access to various tissues because in blood longer.

Front 54

When a cell needs cholesterol, what happens to the synthesis of LDL receptors?

Back 54

Becomes unregulated

Front 55

Which lipoproteins are taken up by the liver for recycling via LDL receptors?

Back 55

IDL and LDL