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!
Crustose Lichen Stage - Xerarch
On bare rocks, conditions are inhospitable for life, as there is extreme deficiency of water and nutrients, great exposure to sun, and extremes of temperature. Crustose lichens alone are usually able to grow in such situations. Some examples of these pioneering species are, Rhizocarpon, Rhinodina, Lecidea and Lecanora. These plants flourish during periods of wet weather and remain in a state of desiccation for very long periods during drought. During the wet weather they rapidly absorb moisture by their sponge-like action. Mineral nutrients are obtained by the secretion of carbon dioxide which, with water forms a weak acid that slowly eats into the rock into which the rhizoids sometimes penetrate for a distance of several millimetres.
Nitrogen is brought by rain or by wind-blown dust. Thus all the life requirements of this simple, crust-like species is met with. Thus, lichens help corrode and decompose the rock, supplementing the other forces of weathering. And by mixing the rock particles with their own remains, make conditions favourable for - growth of other organisms. Thus, a thin layer of soil is formed. The rapidity with which a small amount of soil is formed is controlled largely by the nature of the rock and by the climate. On quartzite or basalt rocks in a dry climate, the crustose-lichen stage might persist for hundreds of years. But on limestone or sandstone in a moist climate, sufficient changes permit the invasion of foliose lichens, and all this may occur within a life time.
Why do protease-supplying cells of the stomach and of the pancreas make only precursors of the active proteolytic enzymes? The stomach and the pancreas make zymogens of the pro
Q. What happens when the oxygen supply is inadequate to maintain aerobic cellular respiration during muscle exercise? If oxygen from myoglobin or hemoglobin is not enough for t
Discuss troponin
Q. Etiology of constipation? The etiology and management of two distinct disorders of the bowel viz., diarrhoea and constipation. We small continue our discussion on certain ot
PEROXISOMES AND GLYOXYSOMES Certain small ovoid unit membrane bound sac like cytoplasmic organelles, resembling lysosomes in size and appearance were isolated from var
Determine the Food Sources of Folate? Folate occurs naturally in foods. Although folate is found in a wide variety of foods, it is present in a relatively low density except i
Cyclosporine Immunosuppressive agent that is selective for lymphocytes mainly "T" lymphocytes. Route: Oral, parental, dose as prescribed. Side-effects: Ne
Q. Causes of reduced Serum HDL levels? Possible causes of reduced Serum HDL levels: - Cigarette smoking - Hypertriglyceridemia - Obesity - Genetic factors - Lack
Write in 3-4 lines about foot examination Foot ulceration and amputation are common and major causes of morbidity and disability in people with diabetes. Skin integrity should
Define about the Simple proteins? Simple proteins are those which contain only amino acids or their derivatives and no prosthetic group. They yield only amino acids or their de
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