Glycerolipid/Sphingolipid Metabolism

Question 1

Cholesterol in the body is either there as a result what 3 things?

Answer 1

1) synthesis; 2) diet; or 3) storage/recycling.

Question 2

In the digestive system,___ ____ and _____ ______ of the stomach help emulsify fats.

Answer 2

• bile acids

- mechanical agitation

Question 3

In the intestines, hydrolysis of fatty acids from fats by ______ (pancreatic ____), yield soapy like substances that help _____ lipids for ______ across the intestinal wall.

Answer 3

• lipases
• lipase
• emulsify
• transport

Question 4

After movement across the intestine, lipids are packaged in _____.

Answer 4

-Chylomicrons

Question 5

Chylomicrons move through the ____ system into the ______ where they get stuck.

Answer 5

• Lymph

- Capillaries

Question 6

Action of _______ _____ in the capillaries removes some of the fat from the ______ and they shrink in size and exit the capillaries and move to the _____.

Answer 6

• lipoprotein lipase
• chylomicrons
• liver

Question 7

Chylomicrons are taken up by the liver and released, when needed as _____.

Answer 7

VLDLs

Question 8

_____ travel the blood system and get converted to ____ and ultimately _____.

Answer 8

• VLDLs
• IDLs
• LDLs

Question 9

Note that cholesterol ONLY gets into cells via ____-_____ ______ of the LDL at the target cell.

Answer 9

-receptor-mediated endocytosis

Question 10

The liver is involved in sensing the body’s need for _____ via ___ ______.

Answer 10

• lipids

- LDL receptors

Question 11

If the liver senses ____ are needed, ____ are packaged by the liver and released. These get degraded by _____ and other enzymes to _____ and ____.

Answer 11

• lipids
• VLDLs
• lipases
• IDLs
• LDLs

Question 12

If the liver LDL receptor cannot detect ____ in the blood, it continues to release more lipids in ______ _____, such as chylomicrons, thus elevating the _____ concentration in the ____.

Answer 12

• LDLs
• lipoprotein complexes
• LDL
• blood

Question 13

_______ _______ drugs target ___-____ ________. These drugs are called _____ (for example, lovastatin) and they stop the pathway that leads to ______.

Answer 13

• Endogenous synthesis
• HMG-CoA Reductase
• Statins
• Cholesterol

Question 14

LDLs are the complexes containing cholesterol that cause problems when they are present in ____ amounts.

Answer 14

high

Question 15

Damage to LDLs can result ultimately in formation of an ________ _______.

Answer 15

atherosclerotic plaque

Question 16

When attacked by reactive oxygen, ______ _____ ____ inside the LDL become oxidized, causing them to be “stickier” to _____ and causing attack by the _____ _____. Ultimately this can lead to a ______.

Answer 16

• unsaturated fatty acids
• arteries
• immune system
• plaque

Question 17

Cholesterol is a metabolic precursor of bile salts, such as _____, ________, and ________. These are made by introducing ____ groups and oxidization to produce _____ groups.

Answer 17

• cholate
• deoxycholate
• taurocholate
• OH
• carboxyl

Question 18

Bile acids/salts are effective _______ to help solubilizie lipids, such as fat, in the diet.

Answer 18

detergents

Question 19

Cholesterol is a precursor of _______.

Answer 19

pregnenolone

Question 20

Pregnenolone is a precursor of the _____ ______.

Answer 20

steroid hormones

Question 21

List 5 steroid hormones

Answer 21

corticosteroids, aldosterones, progesterones, estrogens, and androgens (last two are female and male sex hormones)

Question 22

Estrogens have a ____ ____ that is made from ______ via catalysis by an enzyme called ______.

Answer 22

• benzene ring
• androgens
• aromatase

Question 23

Since some tumors respond to ______, one way to treat them is to give a patient _____ ______ which reduce the synthesis of _____.

Answer 23

• estrogens
• aromatase inhibitors
• estrogens

Question 24

_____ ____ is also made from cholesterol. One of the reactions for making ____ __ in the body requires the action of ___ ____.

Answer 24

• Vitamin D
• Vitamin D
• UV light