Complex Lipids II

Question 1

What are the 3 classes of glycerolipids?

Answer 1

• Triacylglycerols (TAGs) - 3 FA
• Glycerophospholipids - 2FA and Headgroup
• Ether Glycerolipids - 1 FA, 1 Ether, Headgroup

Question 2

What is the major store of lipids in the body?

Answer 2

TAG

Question 3

What glycerolipids are involved in signal transduction?

Answer 3

• DAG (diacylglycerol)

- Arachondonic acid

Question 4

Sphingomyelin, phosphatidylcholine, and glycerolipids can be found where in the cell?

Answer 4

Often found in the outer leaflet of the membrane, associated with cell-cell recognition

Question 5

Phosphatidylserine, Phosphatidylethanolamine, Phosphatidylinositol can call be found where?

Answer 5

Often found in the inner leaflet of the membrane

Question 6

Cleavage of Phosphatidylinositol by phospholipase A1 would result in what products?

Answer 6

• Saturated Fatty acid

- glycerol backbone with unsaturated fatty acid with a 1-phosphoinositol head group left

Question 7

What is the position of the ether in ether glycerolipids?

Answer 7

1 position on the glycerol

Question 8

What are two types of ether glycerolipids?

Answer 8

• Plasmalogen

- PAF (Platelet activating factor)

Question 9

Where can Plasmogens be found?

Answer 9

• Mitochondrial Lipids
• Myelin
• Muscle

Question 10

What is PAF?

- What does it do?

Answer 10

• Platelet Activating Factor, released from phagocytic blood cells in response to stimuli

Causes:

• Platelet aggregation
• Edema
• Hypotension

Question 11

What do you need to synthesize PAF?

Answer 11

• NADPH, AcylCoA, DHAP, activated ethanolamine

* these things take energy to make

Question 12

What are the 3 major sphingolipid components of the plasma membrane?

Answer 12

• Sphingophospholipids

- Glycolipids

Question 13

What types of problems arise when sphingolipids can’t be broken down?
- Where is this defect usually found?

Answer 13

• Neural defects often arise because these are prominent in neural tissue
• Lysosome - usually the location of degradation issues

Question 14

T or F: both types of sphingolipids have fatty acids linked to them.

Answer 14

True - this fatty acids amide linkage to sphingosine is called ceramide

Question 15

T or F: sphingolipids are involved in cell-cell, cell-matrix interactions.

Answer 15

True

Question 16

T or F: Spingolipids responsible for the A, B, and O blood types.

Answer 16

True

Question 17

What does a glycolipid consist of?

Answer 17

• Ceramide connected to a sugar

Question 18

T or F: The glycolipids contain phosophdiester linkages between the sphigosine backbone and ceramide.

Answer 18

False, glycolipids simply have a sugar connected to ceramide

Question 19

What if the variable factor between different glycolipids?

Answer 19

Carbohydrate head groups only

Question 20

What is attached to a ceramide group to make sphingomyelin?

Answer 20

Phosphocholine

Question 21

What is mucolipidosis?

Answer 21

• Inability to degrade glycolipids and sphigomyelin in membranes

Question 22

What are some examples diseases that cause mucolipidosis?

Answer 22

• Gaucher’s Disease
• Tay-Sachs Disease
• Fabray’s Disease

Question 23

Cerebrosides, gangliosides, sulfatides, and globosides are all examples of what?

Answer 23

Glycolipids

Question 24

T or F: glycolipids contain phosphate

Answer 24

False

Question 25

Where are glycolipids most predominant?

Answer 25

Especially predominant in neural cell types

Question 26

What are the two classes of acidic glycolipids? | - what is their charge at physiological pH?

Answer 26

- Sulfatides (sulfate added) - Gangliosides (NANA group added) Negatively charged at physiological pH

Question 27

Where does glycolipid synthesis and breakdown occur?

Answer 27

Synthesis: ER and Golgi Breadown: Lysosome

Question 28

What adds sulfate groups to sugars to make sulfatides?

Answer 28

PAPS

Question 29

How are sugars added to ceramide to make glycolipids?

Answer 29

- Sugar is activated with UDP or CMP then added

Question 30

What kind(s) of bond(s) link(s) fatty acids in sphingolipids and glycolipids?

Answer 30

Amide (NOT ester or ether)

Question 31

What is needed to synthesize ceramide?

Answer 31

``` Serine Palmitoyl-CoA FACoA NADPH FAD ```

Question 32

What kind of environment is needed for lysosomal acid hydrolases to work?

Answer 32

Low pH

Question 33

What happens if sphingolipid degradation is blocked in sphingolipids?

Answer 33

- Synthesis will continue | - You will get an accumulation of degradation products