Lecture 32 - Lipid Metabolism I Flashcards
(37 cards)
Lingual and gastric lipases digest _____fatty acids.
a. long chain (> 12 C)
b. short chain (
b. short chain
Emulsification of fats occurs by suspension within ______.
a. cholymicrons
b. bile salts
b. bile salts
Which of the following is responsible for contraction of the gallbladder?
a. bile releasing enzyme
b. renin
c. secretin
d. cholecystokinin
d. cholecystokinin
(chole-gallbladder; cysto-bladder (the gallbladder is a pouch; kinin-think “kinetic”, it moves the gallbladder to secrete bile)
T/F: After emulsification, the bile salt/FA mixture becomes the substrate of pancreatic lipases?
True
What hormone stimulates the release of bicarbonate to neutralize the acidic pH of bile salts?
secretin
True/False: pancreatic lipase is specific for short chain fatty acids.
False. Pancreatic lipase digests all lengths of FAs
2-Monoacylglycerol (2-MAG) is produced when lipase cleaves _______.
A. TAGs
B. cholesterol
C. phospholipids
A. TAGs
_____ removes FA from phospholipids.
A. pancreatic lipase
B. phospholipase A2
C. esterase
B. phospholipase A2
The pancreas secretes _____, which cleaves fatty acids from cholesterols.
A. pancreatic lipase
B. phospholipase A2
C. esterase
C. esterase
Following cleavage from glycerol, FAs are absorbed into the ________.
A. Portal hepatic bloodstream
B. Liver
C. Intestinal epithelium
C. Intestinal epithelium
Once in intestinal epithelium, short/medium FAs are packaged into _____.
A. LDLs
B. HDLs
C. cholymicrons
D. micelles
D. micelles
Dietary lipids within micelles also contain:
cholesterol, fat soluble vitamins, and phospholipids
Within intenstinal epithelium, FAs and 2-MAG is condensend in the ____ to form _____.
smooth ER;
TAGs (resynthesized)
*TAGs broken down for transport, then reformed
After TAG is resynthesized in the intestinal epithelium, it is packaged into ______, which contain proteins, phospholipids, cholesterol, and other fat soluble vitamins.
A. chylomicrons
B. apoproteins
C. miscelles
A. chylomicrons
A ____ is a blood transport molecule forlipids
chylomicron
Chylomicrons are secreted into the lymphatic system via what process?
exocytosis
Liver cell receptors recognize this protein on chylomicrons, and allows for endocytosis
A. ApoE
B. ApoCII
C. LDL
A. ApoE
Triglycerides are digested by different enzymes dependent upon the _____ of fatty acids.
a. saturation
b. length
d. backbone released from
b. length
Lipoprotein lipase is located on _____ cells of muscle/adipose tissue.
capillary endothelial
Lipoprotein lipase is activated by _____.
A. ApoCII
B. ApoE
C. Chylomicrons
A. ApoCII
What are the three “steps” of utilization of FAs
1) Mobilization - TAGs broken down to FA/glycerol
2) activation - activation and transport to mitochondria
3) Degradation - breakdown of FA to Acetyl CoA
_____ breaks down TAGs to DAGs
ATGL (adipose triglyceride lipase)
____ breaks down DAGs to MAGs
Hormonally Sensitive lipase
MAG is broken down to glycerol and FA by ______
MAG lipase