Exam 3: Lipids

Question 1

What are lipids made of

Answer 1

C, H and O

Question 2

What are the classes of lipids

Answer 2

fatty acids, triaglycerols/ triglycerides, eicosanoids, isoprenoids, lipoproteins

Question 3

What are the 3 kinds of lipoproteins

Answer 3

LDL, HDL, VLDL

Question 4

Are lipids mostly hydrophobic or hydrophillic?

Answer 4

hydrophobic

Question 5

What is the basic structure of fatty acids

Answer 5

carboxyl group + HC tail

Question 6

What is the name of the last C in the fatty acid chain

Answer 6

omega C

Question 7

Explain the main difference between saturated and non saturated fatty acids

Answer 7

non: no double bonds
saturated: has 1+ double bonds

Question 8

Are most fatty acids cis or trans

Answer 8

cis

Question 9

what are the physical properties of saturated and unsaturated fatty acids

Answer 9

sat: solid at room temp
un: liquid at room temp

Question 10

What are trans fatty acids?

Answer 10

have trans double bond conformation

Question 11

What portion of a fatty acid is hydrophobic?

Answer 11

HC chain

Question 12

What do eicosanoids do

Answer 12

autocrine, local signaling

Question 13

What is the precursor for all ecosenoids

Answer 13

arachidonic acid

Question 14

What are the families of eicosanoids

Answer 14

prostaglandin E2, thromboxanes, leukotrienes

Question 15

What do prostaglandins do

Answer 15

signal inflammation and pain

Question 16

What inhibits prostraglandins

Answer 16

NSAIDS, non steroidal anti inflammatory drugs

ibuprofen, aspirin, naproxen

Question 17

What enzyme catalyzes reaction between arachidonic acid and prostaglandin

Answer 17

cyclo oxygenase

Question 18

What is the difference between Cox-1 and cox-2 NSAIDS

Answer 18

cox 1: protects mucus, constitutive

cox 2: inducible, mediates pain, inflammation and fever.

Question 19

What does thromboxane do

Answer 19

platelet aggregation after tissue injury

Question 20

What does leukotriene C4 do

Answer 20

attracts immune cells, broncho constriction, allergy response

Question 21

What are triacylgylcerols what do they do

Answer 21

esters of glycerol, used for energy storage also can act as water repellent

Question 22

What are phospholipids or phosphoglycerides

Answer 22

have a P group at C3, amphipathic, membranes

Question 23

What is the structure of a phospholipid

Answer 23

glycerol with 2 fatty acids attached

Question 24

What do phospholipases do

Answer 24

change the composition of membrane, hydrolyze ester bonds can cleave fatty acids at X group

Question 25

What are isoprenoids made of

Answer 25

repeating isoprene units

Question 26

What are the 2 subclasses of isoprenoids

Answer 26

terpenes:
Steroids:

Question 27

What is an example of a terpene

Answer 27

vitamin K, present in plants, eat your vegetables kids

Question 28

What are steroids from

Answer 28

squalene converted into ring

Question 29

What is the most abundant lipid in organisms

Answer 29

cholesterol

Question 30

What part of cholesterol is hydrophobic? polar?

Answer 30

OH-polar

hydrophobic-bulky part

Question 31

What are lipoproteins

Answer 31

lipids + proteins that can transport hydrophobic lipids around body

Question 32

What are the 4 classes of lipoproteins

Answer 32

LDL: bad, mostly cholesterol
HDL: good, mostly proteins
VLDL: mostly made of triaglycerol
chylomicrons: dietary, mostly made of triacyglycerols and proteins

Question 33

Describe the structure of lipoproteins

Answer 33

ball of of cholesterol and phospholipids on outside, inside made of cholesterol esters, tubes of apolipoproteins

Question 34

What is the function of LDLs

Answer 34

transports cholesterol and cholesterol esters to tissues

Question 35

What is the function of HDLs

Answer 35

collects excess cholesterol from cell membranes or from LDL to liver

Question 36

What is the function of VLDL

Answer 36

transport lipids from liver to tissues

Question 37

In the fluid mosaic model of membrane structure

Answer 37

proteins float in a lipid bilayer