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!
The Exine Layer
It consists of two layers, inner (nexine) which is continuous and an outer (sexine) the sculptured one. The outer layer has ornamentations comprising rod-like bacula showing terminal expansion which sometimes fuses to form a roof like tectum perforated by micropores. During pollen development, the tapetum releases a mixture called tryphine, consisting of carotenoid lipid droplets and fibrogranular proteins into the thecal cavity. These fibrogranular proteins are enclosed in membrane bound cisternae. In tectate pollen, the released substances of tapetum become incorporated on the surface of pollen grains where cisternae membrane ruptures and protein released through micropores enter the tectum and accumulate in the interspaces of bacula.
Pollenkitt is the pigmented lipid fraction left on the surface of the tectum. Unlike intine, the exine held proteins exhibit only one enzymatic activity. The hydration of pollen is described to be stimulatory in releasing the proteins held in the pollen wall layers. The calculated time taken by the exine held proteins of sporophytic origin to pass out is 30 seconds while the intine of gametophytic origin takes a few minutes. This time difference in the protein release has made it easy to collect both samples separately. In SSI systems therefore the rejection reaction is faster than in GSI system.
Explain the functis of the main organelles in plant and animal cell as seen under the lightmicroscope
Temperature is one of the important factors affecting the process of growth in bacteria, as it has a bearing on chemical reactions. The temperature at which the maximum growth occu
Digestion in the Intestine About 2 to 3 liters of alkaline fluid is secreted every day by the intestine and completes the digestive process. Sodium bicarbonate and
Developmental Concepts Unique to Infants and Young Children The cognitive and social emotional development of infants and very young children has unique features. This age rang
Explain colloidal state Foods contain a high percentage of water in which other nutrients present are dispersed. The existence of the colloidal state was first recognized by T
Class of Crustacea - Malacostraca Malacostraca involves most of the larger forms such as crabs, lobsters, shrimps etc. and constitute the majority of crustacean species. The c
Hazards Is an event whether natural or man-made that has potential for causing injury, loss of life and damage to the property or the environment. It can be grouped into two broad
Ensuring Food Safety It is now well-known that the end product inspection and testing does not provide safety of food. It has inherent limitation of mapping the potential ha
what is the general characteristic of aschelminths
tell me the general characters of monopisthocotylea
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