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.
Express the term - Amnion One of the extraembryonic membranes found in terrestrial vertebrate. The amnion is filled with fluid and the developing embryo of reptiles, birds, and
Define Components of Total parenteral nutrition? Glucose: Initiated at the rate of 6 mg/kg/min and increased upto 12-1.4 mg/kg/min, but care to be taken to prevent hyperglyce
How are gametes formed in the pteridophyte life cycle, by mitosis or meiosis? What is the type of meiosis that occurs in pteridophytes? In pteridophytes gametes are made by mit
Q. What are the main cytoplasmic structures present in animal cells? The main cytoplasmic structures of the cell are the centrioles, the cytoskeleton, mitochondria, peroxisomes
Trophic Level - Ecosystem In an ecosystem, the various biotic components are related to each other and form food chains. If we group all the organisms in a food chain accordin
What is market in management term? A market: There is Buyers and sellers for a good or a service come within contact for the function of normally exchange, for money. Lik
Which of the following sugars does NOT contains an O-glycosidic bond? Select one: a. amilose b. amylopectin c. glycogen d. cellulose
Explain what is tooth formula? Ans) Formulae of tooth is (2, 1, 3, 2)
Q. What are the organic chemical groups that describe carbohydrates? How are carbohydrates classified according to the presence of those groups? Carbohydrates are also known as
MCNAUGHTON'S CASE AND LAW: In 1843, McNaughton shot and killed Sir Robert Peel's secretary Edward -Drymmond. It was shown that McNaughton suffered from a number of delusi
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