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

Hemerythrins - respiratory pigments, Hemerythrins - Respiratory Pigments ...

Hemerythrins - Respiratory Pigments The Hemerythrins are rather rare. They take place in some animals belonging to the minor phyla like the sipunculid worms, some brachiopods,

Explain zidovudine, Zidovudine Zidovudine is available alone and in fix...

Zidovudine Zidovudine is available alone and in fixed-dose combinations with lamivudine as Combivir and with lamivudine and abacavir as Trizivir. It can be given in combination

What is biological control, Q. What is biological control? The Biologic...

Q. What is biological control? The Biological control is a natural method to control the size of microorganism, animal or plant populations. The Biological control is based on

Omni science valve-types of valves, Omni Science Valve :  Thi...

Omni Science Valve :  This is another type of tilting disc valve available from 1978. The cage is made of titanium and disc out of pyrolitic carbon. There have been a

What are the main biological functions of water, Q. What are the main biolo...

Q. What are the main biological functions of water? Water is the basic solvent for chemical reactions of living beings; it is the main means of substance transportation in the

Mechanical isolation, In certain instances differences in the morphology of...

In certain instances differences in the morphology of genitalia between species make it impossible for normal mating to occur, and sympatric species tend to remain isolated. When t

#title.humans and environment., what are the two main pollutants that contr...

what are the two main pollutants that contribute to aci rain

Define about the ultraviolet rays - carcinogenic, Define about the Ultravio...

Define about the Ultraviolet rays - carcinogenic? Ultraviolet rays: There is ample evidence from epidemiological studies that ultra violet rays derived from the sun induce an i

Eukaryote, Eukaryote is the type of cell found in several organisms includ...

Eukaryote is the type of cell found in several organisms including single-celled protists and multicellular fungi, plants, and animals as well; characterized by a membrane-bounded

Basic research terms - nursing research, Basic Research Terms: Some of...

Basic Research Terms: Some of the basic  terms that are defined  in  this section are:  Assumptions Operational Definitions  Variables  Delimitation and Limitation  H

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