Digestion and Absorption

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Pepsinogen (inactive)

Protein

Pepsin (active)

Proteoses

Peptones

(peptides)

HCl

Pepsin



The gastric lipase hydrolyses a small amount of lipids



In infants :

Prorennin (inactive)

Rennin (active)

HCl

Casein (milk protein)

Paracasein

Rennin

Paracasein

Ca Paracaseinate (curd)

Ca²⁺

Ca Paracaseinate

Peptones

Pepsin

Digestion in small intestine: Chyme is mixed with succus entericus,

pancreatic juice & bile juice. Pancreatic juice and bile are released through

the hepato pancreatic duct

a

Action of bile: Bile helps in digestion by emulsification (conversion

of fat into micelles or tiny droplets). It provides large surface area

for the action of lipase on fat. Bile also activates lipase.

b

Action of pancreatic juice: Amylopsin (Pancreatic amylase)

hydrolyses remaining starch into disaccharides.

Starch

Amylopsin

¾¾¾¾¾® Maltose + Isomaltose + limit dextrins Enterokinase

(Enterokinin) secreted by intestinal mucosa activates trypsinogen

to

active

trypsin.

Trypsin

activates

chymotrypsinogen

&

procarboxypeptidase

c

c) Pancreatic juice contains : Trypsinogen, Chymotrypsinogen,

Amylases, Lipases, Procarboxypeptidase, nucleases [NEET 2017]