Pollen biology, Biology

Assignment Help:

Pollen Biology

Fluorescence microscopy coupled with biochemical analysis has helped resolve the differential activity of the enzyme, β-l, 3- glucanase that catalyses the dissolution of callose. The enzyme activity is relatively low during the first meiotic division but reaches its peak at the time of spore release. This sequence of events controlling the enzyme activity is important, as an early dissolution of callose may lead to sterility. Use of autoradiographic and fluorochromatic techniques demonstrated the reduced permeability of the callose wall and the resultant chemical isolation of microspores.

A combination of phase-contrast and fluorescence microscopy also revealed that the callose wall during exins formation serves as a mold or template. Factors that trigger the onset and regulation of meidsis in anther and ovule can be worked out by employing labeled reagents. Biochemical studies through isoenzyme markers have already demonstrated specific stages of meiotic process. There is an increase in the activity of acid phosphatase at zygotene, followed by subsequent decline. At pachytene, marked activation of endonucleases is recorded. Isoperoxidases serve as markers in normal pollen development in Mercurialis annua.


Related Discussions:- Pollen biology

Define multiple tube fermentation test, Define Most Probable Number Test (M...

Define Most Probable Number Test (Multiple Tube Fermentation Test)? Presence of coliforms in the water sample can be detected by performing multiple tube fermentation test whic

Role of glucocorticoids in controlling gene expression, Define Role of Gluc...

Define Role of Glucocorticoids in controlling gene expression? Glucocorticoids are another class of hormones involved in the regulation of lipogenic enzymes, but their role in

Epidemiological association between hemophilia and HIV, What is the epidemi...

What is the epidemiological association between hemophilia and HIV infection? As hemophilic patients need frequent transfusions of clotting factors (VIII or IX) they are more s

Biodiversity and economics, With the survival and well-being of humans bein...

With the survival and well-being of humans beings so heavily dependent on biodiversity, its economic value assumes considerable importance. For instance the economic value of ecosy

What are the amphibian features, Q What are the amphibian features that mak...

Q What are the amphibian features that make them dependent on water to survive? Permeable skinexternal fecundation, body subject to dehydration, larval stage and eggs without s

Louping ill, Louping ill This is an infectious encephalomyelitis of sh...

Louping ill This is an infectious encephalomyelitis of sheep and man occurring during spring and summer when the vectors like ticks are active. It is reported from British Isl

Amoebae - protozoan, Amoebae - Protozoan Amoebae may be naked or enclo...

Amoebae - Protozoan Amoebae may be naked or enclosed in tests or shells. The marine, freshwater and parasitic naked amoebae have large commonly tubular lobopodia or fine strap

Tree, what is a seed?

what is a seed?

Responses of plants to stress, Responses of Plants to Stress You know ...

Responses of Plants to Stress You know that certain plant species can grow in severe environmental extremes. For example, plants grow below 0°C in the Himalayas and above 45°C

What is concepts of chromosome, Q. What is the relation between the concept...

Q. What is the relation between the concepts of chromosome and chromatin? Are heterochromatin and euchromatin part of chromosomes? Every filament of chromatin is a complete DNA

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