Define proteins as biological buffers, Biology

Assignment Help:

Define Proteins as biological buffers?

Proteins have the ability to accept or donate hydrogen ions and by doing so they serve as biological buffers. In blood, there are three important buffering systems - plasma proteins, haemoglobin and carbonic acid bicarbonate. The equilibrium reactions for each of these buffering systems are as follows:

1549_Define Proteins as biological buffers.png

The first of these buffering systems, the plasma proteins, functions as a weak acid1 salt buffer when the free carboxyl groups on the protein dissociate, or as a weak base/salt buffer when the free amino groups dissociate. Although the buffering ability of the plasma protein is extremely important in maintaining blood pH, it is not as important as the other two systems, the second buffering system, carbonic acid-bicarbonate, is extremely effective because there are reactions which follow this equilibrium which will regulate either acids or bases.

The H2CO3 level in plasma never goes too high because it is in equilibrium with CO2 (H2CO3 → CO2 + H2O), which is expired by the lungs. In blood, this equilibrium proceeds very quickly because of the presence of carbonic anhydrase, an enzyme found in red blood cells which catalyze it. If the carbonic acid-bicarbonate reaction goes in the opposite direction, the concentration of the HCO3- so formed will be regulated by the kidneys. The third important buffering system in blood results from haemoglobin. Haemoglobin has six times the buffering power of the plasma proteins. It functions well as a buffer because it is present in large amounts, it contains 38 histidine residues (Histidine residues are good buffers because they can dissociate to H+ and the imidazole group) and because haemoglobin exists in blood in two forms, reduced haemoglobin and oxy haemoglobin. It is thus a weaker acid and a better buffer.

 


Related Discussions:- Define proteins as biological buffers

Name the drugs will help relieve for patient x, Patient X has blood plasma ...

Patient X has blood plasma levels of Parathyroid Hormone (PTH) that are always very high due to a tumor consisting of Parathyroid Gland cells that secrete high levels of PTH into t

Describe a health issue or disease, Describe a health issue or disease and ...

Describe a health issue or disease and recommend an intervention (you may utilize the health issue . Justify the intervention level (primary, secondary and tertiary) and setting ch

Intracellular digestion, Intracellular Digestion We all know that unic...

Intracellular Digestion We all know that unicellular organisms do not have a separate alimentary canal system. All the functions of life are carried out inside a single cell.

Determine the initiation of muscle contraction, Describe the Capillarity Th...

Describe the Capillarity Theory in respect of ascent of water in plants. Name the tissue included. Determine the initiation of muscle contraction. What is the role of Sarcoplas

Digestive system in planarias, Q. How are nutrients distributed through the...

Q. How are nutrients distributed through the digestive system in planarias? Planarias have single opening digestive system incomplete with ramifications that transport nutrient

Plasma and its composition, PLASM A - It is slightly alkaline non-l...

PLASM A - It is slightly alkaline non-living intercellular substance which constitutes about 60% part of the blood. It is a pale yellow but transparent and clear fluid.

Explain the reproductive system, Explain the Reproductive System? The h...

Explain the Reproductive System? The human reproductive system produces not only reproductive organs and gametes, but also sex hormones, which have far-reaching effects on huma

Horizontal chart - organization chart, Horizontal Chart: Horizontal ch...

Horizontal Chart: Horizontal chart which read from left to right are occasionally used. The pyramid lies horizontally instead of standing in the vertical position. The line of

Types of drug action, TYPES OF DRUG ACTION - 1 .       PHARMACODYNAMI...

TYPES OF DRUG ACTION - 1 .       PHARMACODYNAMIC DRUGS - These drugs modify the physiological and biochemical processes in the patient's body to eliminate the disease.

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