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

Glands associated with eyes, GLANDS - 1 .       LACRYMAL GLANDS - ...

GLANDS - 1 .       LACRYMAL GLANDS - Tear glands numbers are 3. Its secretion is aquous & salty, keeps eye ball wet, give nourishment to cornea. Lysozyme also present

What is the normal duration of the menstrual cycle, Q. What is the normal d...

Q. What is the normal duration of the menstrual cycle? How does the calendar contraceptive method work? The normal duration of the menstrual cycle is 28 days but it can vary am

Overturn - thermal stratification, Overturn - Thermal stratification T...

Overturn - Thermal stratification The summer or winter stratification is seasonal. Circulation of lake water occurs twice a year, in the spring and autumn (fall) seasons by a

Micro debrider-therma-fill, Micro Debrider: long , it's tip as hand spr...

Micro Debrider: long , it's tip as hand spreader, not smooth and resemble H file. -    These instruments have a hedstrom cutting configuration with a standard 0.02 taper and

How to reduce the stresses on the implant, How to reduce the stresses on th...

How to reduce the stresses on the implant i) There is need to reduce the stresses on the implant - ii) Frequent recall for maintenance or hygiene appointments. iii) Gingi

Is total volume of the reaction is 30 micro liters, You have a 10x enzyme b...

You have a 10x enzyme buffer that you are to use in a particular reaction. The total volume of the reaction is 30 micro liters. How much of the 10x buffer should you add so that th

Features of plant hormones, Features of Plant Hormones The following a...

Features of Plant Hormones The following are the important features of the role of plant hormones in growth and development: The hormone may initiate one response

Male gamete and the female gamete in a flowering plant, What is (a) the mal...

What is (a) the male gamete, and (b) the female gamete in a flowering plant?   (a) The male gamete in a flowering plant is the pollen grain (strictly, the gamete is the male

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