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Flashcards in Complex Lipids Deck (65):
1

What are the 3 main functions of Triacylglycerides?

Energy
Insulation
Buoyancy (whales)

2

Trihydric alcohol is related to what part of a TAG?

Glycerol backbone

3

The esterfication of glycerol with fa what would be the product?

TAG

4

What does saponification mean?

Treatment with alkali

5

The saponification of triacylglycerols leads to the formation of?

hydrolysis and formation of fatty acid salts or soaps.

6

In TAG synthesis we want to produce glycerol phosphate. From what biochemical cycle is the glycerol phosphate come from?

Glycolysis via oxidation of DHAP or phosphorylation of glycerol by glycerol kinase.

7

The final destination of TAGs (2)

Liver: packaged into VLDLs
Adipocytes: packed into nearly anhydrous lipid droplets.

8

What are the membrane lipids?

Phospho and Glycolipids

9

Polar membrane lipids are known to have this special property?

Amphipathic - having polar group on one end and a hydrophobic group at the other.

10

How do we synthesize Phospholipids?

A phosphate esterfied to glycerol or sphingosine

11

Sugars esterfied to glycerol or sphingosine is known as?

Glycolipids

12

Name the two classes of phospholipids

Glycerophospholipids
Sphingolipids

13

What are the non polar membrane lipids?

Sterols

14

What makes up a Glycerophospholipid?

Glycerol
2 FA
Phosphate
Alcohol

15

Sphingolipids are composed of?

Sphingosine
FA
Phosphate
Choline

16

Are glycerophospholipids: non polar, polar, highly polar

Highly polar

17

Name a glycerophospholipid

Phosphatidic Acid
Phosphatidylcholine

18

What is a second type of a glycerophopholipid group

Ether Lipids - ether linkage instead of an ester linkage.

19

What is considered one of the most potent bioactive molecules synthesized and released by a variety of cells?

Platelet Activating Factor PAF

20

What cells does PAF activate?

Inflammatory

21

Sphingosine has what type of long chain backbone? Instead of?

Amino alcohol backbone instead of glycerol backbone

22

The fatty acid also has a different linkage in a sphingosine. What is the difference?

Amide linkage not ester

23

In what tissues do we find spingolipids?

Neural and non neural tissues.

24

When X = H for spinghosine what is the name of that sphingolipid?

Ceramide

25

Name another important Sphingolipid found in a lot of neural tissue

Sphingomyelin

26

What type of acid is made during the synthesis of TAGs

Phosphatidic acid

27

Phosphatidic acid can make 2 different compounds. What are they?

CDP-diacyclglycerol to attach glycerol to inositol
CDP-alcohol -choline, or -ethanolamine

28

What can be made from choline and ethanolamine directly?

PC and PE

29

What is the name of the major surfactant in the lungs and what does it allow for?

DPPC or dipalmitoyl phophatidyl choline allows for ease of alveolar inflation and prevents its collapse

30

DPPC is secreted by what type of cells?

Type II Pneumocytes

31

What syndrome is related to surfactant production? Is it too much or too little surfactant secretion?

Respiratory Distress Syndrome RDS in perterm infants with insufficient surfactant production.

32

A fetus must get to how many months for adequate production of surfactant?

8

33

What can accelerate lung maturation in a fetus?

Giving the mother glucocorticoids shortly before delivery

34

What is another method to prevent and treat infant RDS?

Giving natural or synthetic surfactant by intratracheal infusion

35

Humans cannot synthesize enough of this amino acids to cover our needs and this is an essential nutrient of the body?

Choline

36

A Salvage Pathway involves either these two processes?

1. Decarboxylating phosphatidyl serine or
2. Exchanging serine in PS with Ethanolamine

37

Exchanging serine in PS with Ethanolamine is followed by these 3 chemical processes:

SAM mediated methylations

38

Why do we need Phosphatidyl Inositol?

It serves as a reservoir of arachidonic acid in membrane and provides the substrate for prostaglandin synthesis.

39

Phosphatidyl inositol is synthesized from what?

Free Inositol and CDP-diacylglycerol

40

What type of acid does phosphotidyl have on carbon 1 of its glycerol? carbon 2?

C1: Stearic Acid
C2: Arachidonic Acid

41

The phosophorylation of membrane-bound phosphatidylinositol produces this compound?

Phosphatidylinositol 4,5-bisphosphate (PIP2)

42

What enzyme can degrade PIP2?

Phospholipase C

43

Why does the degradation of PIP2 occur?

In response to a variety of neurotransmitters, hormones, and growth factors to receptors on the cell membrane

44

The product of the degradation of PIP2?

1,4,5- triphosphateinositol and diacylglycerol

45

1,4,5- triphosphateinositol and diacylglycerol mediate what important cell functions?

The activation of intracellular calcium and protein kinase C

46

How can some specific proteins attached to membrane bound glycosylated phophatidylinositol GPI?

Covalently attached via a carbohydrate bridge

47

Being attached to a membrane lipid allows GPI-anchored protein to do what?

Lateral mobility on the surface of the plasma membrane

48

How can the protein be cleaved off its anchor?

By the action of phospholipase C

49

What is the function of GPI?

Anchors proteins to the cell so it could travel the membrane interrogating the extracellular space.

50

For the disease Paroxsymal nocturnal hemoglobinuria (PNH) the most common enzyme that is defective is?

PIGA
phosphatidylinositol glycan A

51

Where is the gene that codes for PIGA located?

X Chromosome

52

What does a phospholipase recognize?

An intact phospholipid

53

Phospholipase A1 does what?

Hydrolyzes the C1 ester, releasing a fa

54

What is the function of Phospholipase A2?

Hydrolyzes the C2 ester

55

Where is Phopholipase A2 prevalent and what is it important for?

In tissues, pancreatic juice.
Important for release of arachidonic acid

56

What will inhibit Phopholipase A2?

Glucocorticoids ex: Cortisol

57

What is a major structural lipid found in membranes?

Sphingomylelin

58

Sphingomyelin is initially synthesized using what two things?

Palmitoyl-CoA
Serine

59

Where is sphingomyleninase's found?

Lysosome

60

Sphingomyelininase initiates degradation by removing what group of the sphingomyelin? what does it leave behind?

Phophorylcholine leaving a ceramide

61

What breaks down a ceramide?

Ceramidase

62

What makes up a Neutral Glycosphingolipid?

A glucose or galactose or other neutral carb + ceramide

63

What part of the Neutral Glycosphingolipid is the hydrophobic tail?

Ceramide

64

An oligosaccharide containing one to several acidic sugar derivatives attached to ceramide makes what?

Acidic Glycosphingolipids

65

Where are Acidic Glycosphingolipids catabolized?

The Lysosomes