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Flashcards in Complex Lipid Metabolism Deck (64):
1

Free fatty acids are a major component of membranes. True or false?

false; minor component

2

Fatty acids are ___ ___ acids

aliphatic carboxylic

3

Describe aliphatic carboxylic acids

generally long, unbranched, even number of carbon chains, length is usually 12 - 24, saturated FAs

4

Saturated fatty acids contain no C=C double bonds. True or false?

true

5

T C=C double bonds found in nature are what orientation

cis

6

In regards to major complex lipids, Triacylgycerols (TAG) have 3 acyl groups in ___ linkage to a molecule of glycerol

ester

7

In regards to TAG, the storage of fatty acids is primarily in ___ tissue but also found as lipid droplets in many cell types

adipose

8

Phosphoglycerides (phospholipid) have a glycerol backbone. Describe this backbone.

two fatty acid molecules attached in ester linkage and a phosphate on the third hydroxyl glycerol. The phosphate is usually esterfied to another alcohol

9

Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phospatidylinositol, and cardiolipin are all what?

phospholipids

10

Plasmalogens are an alkyl alcohol attached via an ___ linkage on position ___ of the glycerol

ether; 1

11

True or false? there may be plasmalogen forms of PC

true

12

Where are plasmalogens synthesized?

peroxisomes

13

This is a phospholipid that does not contain glycerol

sphingomyelin

14

Sphingomyelin is synthesized from what?

amino alcohol spingosine

15

Glycosphingolipids (not phospholipids) are composed of what?

sphingosine, a fatty acid, and one or more carbohydrate or carbohydrate derived structure

note: a sphingosine plus a fatty acid is called a ceramide

16

Galactosyl ceramide is an example of what?

glycosphingolipid

17

Addition of more carbohydrates and sialic acid to produces more complex glycosphingolipids known as ____

gangliosides

18

Synthesis of both TAG and phoshoglycerolipids require what?

glycerol-3-phosphate

19

In regards to TAG synthesis, what two sources is glycerol-3-phosphate derived from?

1.dihydroxyacetone phosphate (glycolytic intermediate)
2. the liver and intestine can obtain it directly from glycerol

20

In regards to TAG synthesis, the enzyme glycerol kinase is expressed primarily in ___ and ___

liver; intestine

21

____ acid is a common intermediate in the synthesis of TAG and phospholipid

phosphatidic

22

TAG synthesis occurs in most tissue, but is most active in ___, ____, and ____

liver; adipose; intestine

23

True or false? In regards to TAG synthesis, all tissues can utilize the phosphatidic acid pathway

true

24

In the phosphatidic acid pathway, what happens to phosphatidic acid

it is dephosphorylated and a third acyl group is added

25

In regards to TAG synthesis, this pathway occurs only in the intestinal mucosa

monoacylglycerol pathway

26

In regards to TAG synthesis - specifically, the monoacylglycerol pathway, MAGs are absorbed from where?

from digestive products in the gut

27

TAG produced in the ___ may include fatty acyls from the diet, or produced from excess carbohydrate and protein

liver

28

TAG produced in the liver will be packed for secretion as ____

VLDL

29

True or false? Most of fatty acid synthesis occurs in adipose tissue

false; very little

30

The TAGs produced in adipose will be stored as __ ___

lipid droplets

31

Fatty acids in the intestinal mucosa are from where?

the diet

32

TAGs in the intestinal mucosa are packaged as ____ for distribution

chylomicrons

33

Muscle cells obtain their fatty acids from the TAG circulating from ___ and from ___

diet; liver

34

TAGs are stored as __ ___ in muscle cells

lipid droplets

35

In regards to phospholipid synthesis, all tissues except mature ___ ___ cells synthesize phospholipids

red blood

36

In regards to phospholipid synthesis, specifically synthesis of phosphatidylcholine, choline is activated by ______ followed by addition of ___ from ___

phosphorylation; CMP; CTP

37

In regards to phospholipid synthesis, specifically synthesis of phosphatidylethanolamine, the CDP-choline is added to what?

1,2-diacylglycerol

38

In regards to phospholipid synthesis, phsophatidylserine is produced primarily by exchanging ___ for the ___ of PE

serine; ethanolamine

39

In regards to phospholipid synthesis, specifically the synthesis of phosphotidylinositol and cardiolipin, phosphatidic acid has to be "activated" by formation of ___-___

CDP-diaglycerol

40

In regards to phospholipid synthesis, specifically Dipalmitoylphosphatidylcholine, is secreted by certain types of ___ cells as the major lipid component of ___ ___

lung; lung surfactant

41

Dipalmitoylphosphatidylcholine is found in the extracellular fluid lining the ____

alveoli

42

Dipalmitoylphosphatidylcholine is composed of ___% lipids, and ____% proteins

90; 10

43

Surfactant decrease the surface tension, reducing the pressure needed to do what?

reinstall the alveoli

44

Reduced ability to synthesize and/or secrete surfactant is associated with what?

respiratory distress in premature infants

45

This is a special glycerol ether phospholipid formed by blood cells

Platelet activating factor

46

In regards to phospholipid synthesis, specifically platelet activating factor, induces platelet aggregation at ___ concentrations

low

47

In regards to phospholipid synthesis, Sphingomyelin is formed from what two things?

palmitoyl-CoA and Serine

48

Sphingosine + fatty acyl in amide linkage = ?

ceramide

49

In regards to glycosphingolipids, a ceramide + one carbohydrate residues is called what?

cerebroside

ex: galctoceramide, glucosylceramide

50

In regards to glycosphingolipids, a ceamide + 2 or more carbohydrates is called what?

globoside

51

In regards to glycosphingolipids, gangliosides contain a globoside and one or more molecules of a ___ acid

sialic

52

Phospholipase A2 is secreted by the ___ as a digestive enzyme

pancreas

note: also found in snake venom; Phospholipase C and D are signaling components

53

In regards to turnover of gangliosides, these are specific lysosomal enzymes involved in the catabolism of sphingolipids

sphingolipidoses

54

Genetic deficiency of any sphingolipidoses causes what?

sphingolipidosis (accumulation of specific lipid)

55

Tay-Sachs disease is caused by a deficiency in what?

B-hexosaminidase A

note: causes accumulation of Gm2

56

In regards to turnover of gangliosides, What are the symptoms of Tay-Sachs disease?

rapid, progressive and fatal neurodegeneration; blindness; cherry-red macula; muscular weakness; seizures

57

In regards to turnover of ganliosides, Gaucher is found in 1/1000 Ashkenazi Jewish Persons. It is caused by a deficiency in what?

glucocerbrosidase

note: causes accumulation of glucocerbroside

58

What are the symptoms of Gaucher?

hepatosplenomegaly, osteoporosis of long bones, severe neurological signs

59

Phosphatidylethanolamine is a ____

plasmalogen

60

Phospholipase A1 hydrolyzes what bond in a phospholipid?


O - C - R1
^

61

Phospholipase A2 hydrolyzes what bond in a phospholipid?

R2 - C - O
^

62

Phospholipase B hydrolyzes what bond in a phospholipid?

same as both A1 and A2

63

Phospholipase C hydrolyzes what bond in a phospholipid?

O - P - O - N base
^

64

Phospholipase D hydrolyzes what bond in a phospholipid?

O - P - O - N base
^