Lipids/Fatty Acids Flashcards Preview

MCAT biochemistry > Lipids/Fatty Acids > Flashcards

Flashcards in Lipids/Fatty Acids Deck (30):
1

the roles of lipids are

triglycerides (fat) store energy
phospholipids create barrier between intracellular and extracellular environments
cholesterol serves as building block for hydrophobic steroid hormones

2

structure of fatty acids are typically

long unsubstituted alkane that end in carboxylic acids that are 14 to 18 carbons long

3

saturated fatty acid is when

there are no alkenes in the chain
all carbons are covalently bonds to maximum amount of hydrogens

4

unsaturated fatty acids is when

there is an alkene or more present in the chain
these bonds are always Z formation

5

micelle

depicts fatty acid hydrophobic interaction by creating a solvation shell around hydrophobic tail region on the fatty acid while the hydrophilic head is on the outside

6

triacylglycerols (TG) are composed of

three fatty acids esterifiedd to glycerol molecule

7

glycerol has three charon thiol with formula of

HOCH2-CHOH-CH2OH

8

lipase enzyme

hydrolyze fats

9

fats are efficient energy storage because of two reasons...

packing and energy content

10

terpenes are class of molecules built from

isoprene units (C5H8) with general formula of (C5H8)n

11

monoterpenes contain

two isoprene units

12

sesquiterpenes contain

three isoprene units

13

diterpenes contain

four isporene units

14

squalene is a triterpene used or

biosynthetic manufacture of steroids
and component of earwax

15

terpenoids are functionalized-terpenes built from isoprene skeleton and functionalized with other elements such as

O, N, S, etc
ex: vitamin A (C20H30O)

16

steroids are based on the structure of

cholestrol

17

examples of steroid hormones made from cholestrol are

testosterone and estradiol

18

there are no receptors on steroid hormones because they are

highly hydrophobic thus can diffuse right through lipid bilayer membrane
*steroid receptors are located on target cells rather than on itself

19

peptide hormones (insulin) exert their effects by ______ whereas, steroid hormones exert their effects by______

binding to receptor at the cell-surface
diffusing into cells to find their receptors

20

sphinoglipids are lipids that

have similar structure to phospholipids, except its backbone is made up of sphingosine instead of glycerol

21

important example of a sphongolipid is

sphingomyelin which is component of myelin sheath around neurons

22

waxes are long chains of

esterified fats to a long alcohol chain which are extremely hydrophobic and acts as waterproof barriers
ex: in plants, serum

23

fat-soluble vitamins are characterized by

being absorbed through dietary fat and there are four A, D, E , and K

24

fat-soluble vitamins are stored in

adipose tissue and liver

25

vitamin A is a

terpenoid essential for vision, growth, epithelial maintenance, and immune function

26

vitamin D is a

steroid derived from cholesterol, which is essential in regulating blood levels of calcium and phosphate

27

vitamin E is a

tocopherols (methylated phenols) which is essential for antioxidants

28

vitamin K is a

coenzyme in the activation of clotting proteins

29

prostaglandins are defined by

eicosanoids which are 20-carbon fatty acid

30

prostaglandins role is

dependent to where they bind to but help in regulating smooth muscle contraction in intestine and uterus, regulating blood vessel diameter, maintain gastric integrity by decreasing acid secretion and increasing mucus secretion