Carbohydrate metabolism Flashcards
Digestions is generally completed by the time the stomach contents reach the
Junction of the duodenum and jejunum
In the mouth, dietary carbohydrates are first acted upon briefly by the first enzyme ___
Salivary amylase (Ptylain)
Salivary amylase hydrolyze___ bonds
alpha 1,4 glycosidic bonds
Cellulose contains __ bonds
beta 1,4 glycosidic bonds
In the stomach, CHO digestion is stopped temporarily by the
Low pH of the gastric juice which inactivates salivary amylase
In the small intestines, further CHo digestion is brought about by
Pancreatic a-amylase
Final digestion occurs in the ___
mucosal lining of the upper jejunum
Digestive fluid that acts in the upper jejunum
Succus entericus
Hydrolyzes alpha 1,6 glycosidic bonds to form glucose from oligosaccharides and isomaltose
Isomaltase
Absorption of carbohydrates occurs only in the ___
Small intenstines (duodenum and upper jejunum)
Mechanism for absorption of glucose and galactose
Active transport, needs energy and a carrier protein molecule, and a co-transport system with Na+
Mechanism for absorption of fructose and mannose
Facilitated diffusion (rapid)
Mechanism for absorption pentoses like riboses
Simple diffusion through the lipid bilayer
Fructose specifically uses ___ as it moves from the luminal side towards the inside of the cell and into the serosal side
GLUT 5 (facilitative glucose transporter)
Tissue distribution of GLUT 1
Human RBC BBB BRB BPB BTB