1.15 - Cholesterol

Question 1

What is cholesterol?

Answer 1

short lipid molecule, insoluble in water

Question 2

Where do human gets there cholesterol?

Answer 2

75% produced in liver
25% from food

Question 3

How is cholesterol transported around the blood stream?

Answer 3

transported around blood inside
lipoprotein particles as its insoluble

Question 4

What does High density lipoprotein (HDL) consist of?

Answer 4

cholesterol
phospholipid
triglyceride
apoprotein

Question 5

What does Low density lipoprotein (LDL) consist of?

Answer 5

apoprotein

Question 6

What is HDL?

Answer 6

• “good cholesterol”
• 20% cholesterol
• triglycerides with
  unsaturated fatty acids
• different apoproteins

Question 7

What is LDL?

Answer 7

• “bad cholesterol”
• 40% cholesterol
• triglycerides with
  saturated fatty acids
• apoprotein B

Question 8

Where does HDL transport cholesterol for breakdown?

Answer 8

Liver

Question 9

Where does LDL get transported to and from?

Answer 9

from liver to cells

Question 10

What is cholersterol uptake?

Answer 10

S1: cells have LDL receptors on surface which binds to LDL
S2: LDL bound to receptor is taken up into cell by endocytosis
S3: LDL and LDL receptors are separated at low pH
S4: LDL receptors are recycled back to cell surface
S5: LDL vesicle fuses with lysosome
S6: LDL is degraded and cholesterol is released