Absorption of amino acids and peptides, Biology

Assignment Help:

Absorption of amino acids and  peptides

Generally,  the  dietary proteins are almost comp!etely  digested to their constituent amino acids and these are rapidly absorbed  from  the intestine into the portal blood. Some of the dipeptides are hydrolyzed by peptidases  located in  the absorptive cells so  that only amino acids  are  released  into  the  portal blood.  D-amino acids are absorbed by  simple diffusion but the L-amino  acids (occurring  in  foods) require a carrier system in  the absorption.

The inechanism by which amino acids are absorbed is conceptually identical to that of monosaccharides. The  luminal plasma membrane of the absorptive cell bears  at least  four sodium-dependent amino  acid  transporters (one each  for  acidic,  basic, neutral  and aromatic amino acids). Each system transports amino acids that  are  structurally similar. These transporters bind  amino acids only after binding sodium. The fully  loaded  transporter  then  undergoes  a conformational change that dumps sodium and  the amino acid  into the cytoplasm, followed by  its reorientation back  to  the original  form. Thus, absorption of amino acids  is also absolutely dependent on the electrochemical gradient of sodium across the epithelium. The energy dependent carrier  system  also  involves  vitamin  B6 (pyridoxal phosphate) during the transport of amino acids.

 


Related Discussions:- Absorption of amino acids and peptides

Determine guidelines for planning balanced diets for elderly, Determine Gui...

Determine Guidelines for Planning Balanced Diets for Elderly? The key element in planning diets for the elderly should be nutrient-based dietary guidelines, in order to reduce

Explain the direct surface agar plating method, Explain the Direct Surface ...

Explain the Direct Surface Agar Plating Method? In the direct surface agar plating method, molten agar is placed on to the surface to be assessed. Upon hardening, it is incubat

Colibacillosis of newborn animals, Colibacillosis of newborn animals T...

Colibacillosis of newborn animals This is the commonest disease entity of newborn farm animals. In calves the disease  occurs in three forms, viz. enteric colibacillosis manif

Dietary management for ulcerative colitis, Q. Dietary Management for ulcera...

Q. Dietary Management for ulcerative colitis? Proper dietary management is important for maintaining a good nutritional status of the patient. Long-term management is generally

How do homeotic genes regulate development in drosophila, How do homeotic g...

How do homeotic genes regulate development in Drosophila? Homeotic genes code for regulatory proteins that are thought to control the rate of cell division in various body area

Vitamin - d, VITAMIN - D Also known as Calciferol / Anti ricket vit...

VITAMIN - D Also known as Calciferol / Anti ricket vitamin / sun shine vitamin. It is necessary for bones & teeth. It is synthesized in presence of UV rays of sunl

Main species of taenias that cause human diseases, Q. What are the two main...

Q. What are the two main species of taenias that cause human diseases? The two chief species of taenias that cause disease in humans are Taenia solium, or the pork tapeworm, an

What volume of water to make solution, You need to prepare 500 ml of a solu...

You need to prepare 500 ml of a solution containing 10 mM Tris, 0.15 M NaCl and 1 mg/ml SDS. At your work disposal are stock solutions containing 1 M Tris, 2.5M NaCl and 10% (w/v)

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd