Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Alterations occurring in nuts and oilseeds Some oilseeds have acquired a great significance in the large-scale industrial production of edible oils. You have already studied t
What are nymph and imago? Nymphs are larvae of hemimetabolic insects (like grasshoppers). They are very same to the adult insect although smaller. In holometabolic insects (lik
Q. What do you mean by Herbaria and Museums? A herbarium is a collection of pressed and dried plants arranged according to some valid system of classification and available for
Explain what is Mustard Operation ? The difference in Mustard operation is that either pericardium or polyester patch is used for making the inter atrial baffle. The baffle com
To verify the effect of intra-specific competition on the growth of saplings of Eucalyptus dives, an experiment was designed in which two sets of pots were used. In the first set o
Phylum Zygomycetes 1) Asexual reproduction by non-motile spores produced from a stalked spore case which is known as sporangium. 2) They reproduced by- conjugation between n
Q. What are CD4 lymphocytes? What is the relationship between these cells and HIV? How does HIV replicate? The CD4 lymphocytes are T helper lymphocytes that present in their pl
Q. Are all pneumonias caused by bacteria? The Pneumonia is the generic name of inflammation of the lungs. Moreover bacterial pneumonias, there are pneumonias caused by fungi, v
In the year of 1953, Watson and Crick worked out the 3-D structure of DNA, beginning from X-ray diffraction photographs taken through Wilkins and Franklin. They decreased which D
Which statement is correct? A. Synapomorphies identify monophyletic groups. B. A synapomorphy may arise due to covergent evolution. C. A synapomorphy is an ancestral trait. D. Syna
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd