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.
Define functions of carbohydrate - Protein sparing effect? Carbohydrates help in regulating the protein metabolism. Presence of sufficient carbohydrates to meet energy demands
How can the fact that fishes and dolphins have similar organs and similar general shape be explained? Dolphins and Fishes have similar organs and shape because although they ha
What is the mechanism of lipolysis?
What is omnispective classification
What are the typical vegetation and the typical fauna of the deserts? The predominant fauna of desert ecosystems is produced by reptiles, as lizards and snakes, terrestrial art
Implementation The planned goals and strategies are translated into nursing intervention by means of the nursing care plan. It is essential that the client and family par
What is the location of the salivary glands in humans? There are 6 major salivary glands and they are located one in every parotid gland, two beneath the mandibles (submandibul
Q. Haemodynamic Study of constrictive pericarditis? Simultaneous right and left heart studies are useful. Due to exaggerated waves in atria, W-shaped atrial pressure tracing wi
Blood functions to maintain homeostasis in the human body through all but which of the following: Answer moving carbon dioxide away from cells following completion of aerobic metab
Induction of antimicrobial substances Phytoalexins are antimicrobial substances produced by plants in response to pathogen. They accumulate at the site of infection. For exam
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