Cholesterol

Question 1

Steroids

Answer 1

organic 4 ring (ABCD) stucture

Question 2

Sterols

Answer 2

steroid subgroup w/ hydroxyl group at 3-position of A ring

Question 3

Cholesterol

Answer 3

maintain integrity and fluidity of membranes
component of lipid rafts
precursor for bile salts, steroid hormones, Vit D

Question 4

Free Cholesterol

Answer 4

in membranes of all animal cell membranes

Question 5

Esterified Cholesterol

Answer 5

not in membranes

storage form

Question 6

Where is cholesterol made?

Answer 6

liver, intestine, steroidogenic tissue

Question 7

Sources of liver cholesterol

Answer 7

de novo synthesis
diet
delivered via HDLs

Question 8

Substrates for cholesterol synthesis

Answer 8

Acetyl CoA- C skeleton
NADPH- reducing equivalents
ATP- Energy

Question 9

Gall Stones

Answer 9

from too little bile salts or too much cholesterol in gall bladder

Question 10

Lipoproteins

Answer 10

spherical complex of lipids and proteins

transport cholesterol, fats, fat soluble compounds in plasma

Question 11

Chylomicrons

Answer 11

transport dietary lipids
made in enterocytes in gut cells
largest, least dense, highest % of fat

Question 12

Very Low Density Lipoproteins

VLDL

Answer 12

transport newly made lipids
made in hepatocytes
smaller and more dense
Move fat from liver to peripheral tissues

Question 13

Low Density Lipoproteins

LDL

Answer 13

transport cholesterol to peripheral tissues
highest % cholesterol
carry bad cholesterol

Question 14

High Density Lipoproteins

HDL

Answer 14

transport cholesterol from periphery to liver
carry highest % protein
2nd highest % cholesterol
carry good cholesterol

Question 15

Lipoprotein Composition

Answer 15

Core
Polar Lipid Surface
Aphipathic Apoliporoteins

Question 16

Core of Lipoproteins

Answer 16

neutral lipids- TAG and cholesterol esters

hydrophobic

Question 17

Polar Lipid Surface of Lipoproteins

Answer 17

composed of phospholipid (PC + SM) and free cholesterol

hydrophilic heads

Question 18

Aldosterone

Answer 18

from adrenal cortex

stims renal reabsorption of Na+ and excretion of K+

Question 19

Cortisol

Answer 19

from adrenal cortex
increase gluconeogenesis
anti- inflammatory action
protein breakdown in m

Question 20

Estrogens

Answer 20

control mestrual cycle

promote development of female secondary sex characteristics

Question 21

Progesterone

Answer 21

secretory phase of uterus and mammary glands

implantation and maturation of fertilized ovum

Question 22

Testosterone

Answer 22

stims spermatogenesis
promotes male secondary sex characteristics
promote anabolism
masculinization of fetus