Rejection reaction, Biology

Assignment Help:

Rejection Reaction

For rejection reaction the physiological and biochemical processes are set in the pistil by the recognition reaction specific to the type of pollen that lands on stigma. In contrast to systems where inhibition can occur on stigma itself thus preventing germination of pollen or its entry into style, in GSI system it may occur in style leading to either inhibition of pollen tube growth or its bursting.

The pollen wall and its protein content plays an important role in pollen stigma interaction. Through cytochemical studies it has been observed that the pollen wall is perforated by protoplasmic strands giving the appearance of a living physiological structure playing a very responsible role in the process of interchange between the pollen grain and the substrate. The incorporation of proteinaceous substances in the exine and the intine has been demonstrated by EM studies of the pollen wall during development. A good amount of mobile proteins of the pollen grains is S-gene specific. The recognition proteins of incompatibility are held extra-cellularly in the pollen wall. In GSI plants, these proteins are present in the intine while in SSI plants they occur in the exine.


Related Discussions:- Rejection reaction

Who is fruits useful for diabetics patients, Fruits Diabetics should ha...

Fruits Diabetics should have fruits every day. Be careful to select fruits and fruit juices, citrus fruits, such as oranges, grapefruit should be included. Tell them to eat fru

What are the cytochromes, Q. What are the cytochromes? Cytochromes are ...

Q. What are the cytochromes? Cytochromes are proteins of the interior mitochondrial membrane that are specialized in electron transfer and participate in the respiratory chain.

Alcohol related emergencies, Alcohol Related Emergencies: Alcohol is o...

Alcohol Related Emergencies: Alcohol is one of  the most serious health problems. Alcoholism is defined as a primary or chronic disease with genetic, psychological and environ

Evolution, related words for reproductive isolation.

related words for reproductive isolation.

Laws governing ocular movements, Laws Governing Ocular Movements Herin...

Laws Governing Ocular Movements Hering's Law of Equal Innervation states that equal and simultaneous innervation flows from the brain to yoke muscles in all binocular movement

Treatment and management of chronic bronchitis, Treatment and Management ...

Treatment and Management Diagnosis History, physical examination  Radiological examination chest X-ray  Sputum studies, CIS, smear,  ABG analysis-restin

Respiration, difference between the respiration occurs in lower and higher ...

difference between the respiration occurs in lower and higher organisms

Explain types of dietary adaptations for trerapieutic needs, Types of dieta...

Types of dietary adaptations for trerapieutic needs Normal nutrition is the foundation upon which therapeutic modifications are based. We  have already discussed  in  previous

Explain diseases of pericardium, Q. Explain Diseases of pericardium? Pe...

Q. Explain Diseases of pericardium? Pericardium is the sac covering the heart. Pericardium consists of two layers-the visceral pericardium (epicardium) and the parietal pericar

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