Flashcards in Lipid Digestion Deck (23):
1
What percentage of energy requirement is provided by ingested lipids?
55%
2
What do ingested lipids comprise of?
Fats / Oil, phospholipids, cholesterol and cholesterol esters and fatty acids
3
Describe the solubility of ingested lipids
Insoluble or poorly soluble in water
4
What does gastric lipase do?
hydrolyses one of the 3 fatty acid tails
5
What is the significance of the double bonds and the length of the chains?
The length and strength of the molecule
6
What do fatty acids act as
Surfactant
7
What is CCK
A gut hormone
8
WHat is the role of bile salts
to confer polarity (polar charge) onto lipid molecules, act as detergents to emulsify large lipid drops to small droplets
9
Where are bile salts sectred from
Bile from the gall bladder
10
Bile salts are amphipathic. define this
hydrophilic group and hydrophilic group
11
What happens in failure to secrete bile salts
lipid malabsoption - steatorrhoea (fat in faeces) this can lead to secondary vitamin deficiency due to failure to absorb lipid soluble vitamins (ADEK)
12
What is the main purpose of the bile salts
To increase the surface area for action of lipase
13
What does the increased surface area allow for
Attack by pancreatic lipase
14
What does the increased surface area block?
access of the enzyme to the lipid with the hyrophobic core of the small droplets
15
Where are the final products of lipid digestion stored and released from?
Mixed Micelles
16
Where do short chain and medium chan fatty acids diffuse through>
Enterocyte
17
Where do short chains and medium chain fatty acids exit through?
The basolateral membraine and enter the villus capillaries
18
How long are long chain fatty acids ?
>12 Carbons
19
Where are long chain fatty acids resynthesised?
In the Endoplasmic Reticulum
20
What does Apolipoprotein do
Apolipoprotein coats the lipid mecellls and forms a chylomicron
21
Where does chylomicron enter the systemic circulation and how
into the subclavian vein via through the thoacic duct
22
Where do chylomicron triglyceride metabolised in capillaries by lipoprotein lipase present?
Endothelial cells
23