Lipid classification Flashcards Preview

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Flashcards in Lipid classification Deck (34):
1

What part of fatty acids is hydrophobic?

hydrocarbon chain

2

what part of fatty acids is hydrophillic?

terminal carboxyl group with pKA of 4.8

3

Long chain fatty acids (LCFA) are predominantly..

hydrophobic and must be in association with protein for circulation solubility

4

at phisiological pH (-COOH)...

ionizes to (-COO-)

5

the longer the chain...

the more hydrophobic it becomes

6

Saturated fatty acid

-NO double bonds
-higher energy

7

unsaturated fatty acids

-carbons have 1 or more double bonds (mono- or polyunsaturates)

8

double bonds in unsaturated fatty acids

-cis conformation
-cause kinks
-spaced at 3 carbon intervals

9

double bonds and melting temp

-reduces Tm
-increases fluidity
-prevents it from packing as tightly, can't form solid as easily
-vegetable oil

10

increasing chain length and melting temp

-increasing chain length increases Tm
-decreases fluidity
-lard

11

membrane phospholipids

-typically have LCFA
-contain double bonds to improve fluidity characteristics

12

fatty acid structure naming

-carbon 1=carboxy carbon
-carbon 2-the carbon to which the carboxyl group is attached is called a-carbon
-carbon 3=b-carbon
-carbon 4=gamma carbon
-the terminal methyl group carbon is called the omega carbon independent of chain length

13

omega 3 or 6?
Arachidonic acid 20:4(5,8,11,14)

omega 6

20-number of carbons
4-number of double bonds
numbers in parenthesis-the number of the carbon that each double bond begins at

take number of carbons (20) and subtract the last double bond carbon (14)

20-14=6

14

a-linolenic acid 18:3(9,12,15)
omega 3 or 6?

18-15= omega 3

15

linoleic acid and a-linolenic acid

-humans cannot synthesize this
-get from plants

16

linoleic acid

-humans can't synthesize
-precursor for other shorter omega 6 FA

17

arachidonic acid

-becomes essential IF linoleic acid is deficient in the diet
-substrate for prostaglandin synthesis

18

a-linolenic acid

-humans cannot synthesize this
-precursor for omega 3 FA: important for growth and development

19

short and medium chain FA

4-10 carbons

20

long chain FA

16-22 carbons

21

very long chain FA

>22 carbons
-only present in certain tissues
-nervous system/brain

22

Where is FA synthesis?

cytosol, elongated at the ER, so it needs to be ready in the cytosol

23

2 forms of FA

1.unesterified
2.fatty acyl esters (esterified fatty acids)

24

What are the levels of FA in most tissues?

low?

25

where are there high levels of FA?

blood serum during fasting

26

albumin

transport of long chain FA in blood serum requires association with this

27

point of origin of FA

-TAG in adipose tissue
-from circulating lipoproteins

28

What are the only tissues that would release TAGs in the blood stream?

liver and digestive system ONLY

29

Site of consumption of FA

-most tissues
-a lot in adipose tissue and muscle

30

use of FA

-structural components of membrane
-conjugation to proteins for membrane anchoring properties
-oxidized to produce energy (esp in liver and muscle)
-precursors for hormone like prostaglandins

31

Where are fatty acyl esters stored?

adipose tissue

32

what are fatty acyl esters precursors for?

more complex molecules such as TAGs

33

What serves as the major energy reserve for the body?

fatty acyl ester

34

What are most of plasma FA?

fatty acid esters contained in lipoprotein particles
-TAG
-cholesteryl esters
-phospholipids