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

Primitive arthropods, Primitive Arthropods The primitive arthropods, O...

Primitive Arthropods The primitive arthropods, Onychophora (for example Peripatus) have a series of paired legs which are not jointed but have a ringed appearance because of t

Contractile vacuoles of amoeba, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Zonation in the lake biome, Q. Zonation in the lake biome? Precipitatio...

Q. Zonation in the lake biome? Precipitation that does not evaporate or penetrate the soil remains on the soil surface resulting in run off which flows down from the mountains

Explain process of determination of vitamin B6, Explain process of Determin...

Explain process of Determination of vitamin B 6 Colorimetric determination of indophenol dye using 2,6-dichloroquinone chloraimide as colour reagent or diethyl-p-phenylenediam

Why does thermal inversion increases air pollution, Q. Why does thermal inv...

Q. Why does thermal inversion increases air pollution? What harm can thermal inversion cause to humans? The Thermal inversion confines at low altitude a layer of pollutants tha

Draw a graph for an iv multiple infusion of a drug, Draw A graph for an IV ...

Draw A graph for an IV multiple infusion of a drug, and label on the graph where the trough (predose) blood draw would be collected and where the peak (postdose) blood draw would b

Meaning of diabetes self management education, Q. Meaning of Diabetes Self ...

Q. Meaning of Diabetes Self Management Education? You have learned that the treatment of diabetes depends upon the cooperation of the patient and also on how actively a patient

Digestive system - liver, LIVE R (HEPAR) - Largest gland of body. W...

LIVE R (HEPAR) - Largest gland of body. Weighing 1.6 kg. Form 1/40 of the body weight. Bio-chemical laboratory. Bussiest part in whole river of life. Dark reddish brown

Explain deformaties of the cliest wall should be noted, Explain Deformaties...

Explain Deformaties of the Cliest wall should be Noted a) Pectus carinatum (pigeon chest): may be associated with Marfan syndrome. b) Pectus excavatum: commonly seen in Marfan

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