Bile acids are synthesized from ?
a) Heme
b) Cholesterol
c) Ribulose
d) Arachidonic acid
Correct Answer - B
Ans. is ‘b’ i.e., Cholesterol
Primary bile acids are cholic acid and chenodeoxycholic acid, which
are synthesized from cholesterol in liver.
In the intestine some of the primary bile acids are converted into
secondary bile acids, i.e., deoxycholic acid (formed from cholic acid)
and lithocholic acid (derived from chenodexoxycholic acid).
Glycine and taurine conjugates of these bile acids are called as bile
salts.
For example, cholic acid is a bile acid, and its glycine conjugate
(glycocholic acid) is a bile salt.
Bile salts help in digestion and absorption of fat by emulsification
and micelles formation.
Bile salts act as detergents, i.e., they have surface tension lowering
action.
Detergent action is due to amphipathic nature of bile salts (Note :
Amphipathic molecules are molecules that contain both hydrophobic
non-polar as well as hydrophilic-polar ends).