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.
Two chromosomes in a cell have identical length and centromere position yet are not homologous, what is different about them
The kind of epithelium which forms the inner walls of blood vessels is : 1. cuboidal epithelium 2. columnar epithelium 3. ciliated columnar epithelium 4. squamous epith
Valvular Heart Diseases Normal heart valves function to maintain a uni-directional flow of blood through cardiac chambers. Two basic problems that compromise the normal functi
Baroreceptor activity affects coronary vascular resistance reflexly. With carotid occlusion, baroreceptor hypotension leads to reflex adrenergic stimulation, increased metabolic ac
Fatty acid breakdown brings about the oxidation of long-chain fatty acids. The fatty acids are first transformed to their acyl CoA (coenzyme A) derivatives and then degraded by the
In which areas of the globe is gymnosperm abundance noteworthy? These plants are the typical vegetation of cold regions as the taiga, or boreal forest, of the northern hemisph
Chilling and Flower Induction Some plants flower only after passing a winter season. For example, winter wheat is sown in the autumn for harvest in the following summer. It ne
Q. Concerning volition of the individual how can the reactions of the nervous system be classified? The efferences (reactions) of the nervous system can be classified into volu
Early campaigns of the 19th century that focused on sanitation, hygiene, housing, and nutrition had little effect in controlling communicable disease due to flawed rationale based
What is Ridgemapping The patient is given local anesthesia by infiltration to numb both the facial (labial/buccal) and lingual (palatal) mucosa. Using either a sharp straigh
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