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!
Tolerance to Cold and Freezing Temperatures
In the earlier section you have been studying about tolerance of animals to high temperature. Now in this subsection we will study about tolerance to cold and freezing temperatures. The effects of low temperature are equally perplexing as those of high temperature. Some organisms can tolerate extensive freezing but most animals cannot. Animals that live in '4 temperature and cold regions are often exposed to long periods of winter temperatures that are far below the freezing point of water. Survival of ectothermic animals at such subzero temperature depends upon the physiological and biochemical characteristics that can be described as cold hardiness. An animal can develop cold hardiness either by developing capacity for freeze tolerance or by avoiding ice formation even if exposed to temperatures as low as -40°C to -50°C. The latter are regarded as freeze intolerant.
The intertidal marine invertebrates of colder zones are freeze tolerant in the sense that they survive extensive ice formation within their bodies. Many other animals also survive in spite of extensive ice formation. For example, midge Chironomous larva from Alaska can be frozen and thawed repeatedly without injury. Several species of insects are known to contain high concentration of glycerol in their body fluids. It is well-known that glycerol protects red blood cells and mammalian spermatozoa from injury caused by freezing. Therefore, glycerol is widely used for this purpose and samples of human or bull sperm can be kept frozen and viable for several years using glycerol. Without such treatment, freezing is Iethal, to sperms. Only a few vertebrates tolerate extensive ice formation. Birds and mammals however, are not known to tolerate freezing.
what is bowman''s capsule?
What technique would you use to see if two proteins interact with each other inside of a cell?
What is polymorphism
WORKIN G OF EYE - Human eye is sensitive to light wavelenght ranging from 380 - 760 nm. Bees, ants, spiders and gold fish can see uttraviolet light which is invisible to hu
Maturation Phase The Maturation phase characterizes he transformation of diploid primary spermatocytes into haploid spermatids. The primary spermatocyte divides meiotically t
Explain Supravalvular aortic stenosis murmur? Supravalvular Aortic Stenosis Murmur : Characteristic: Murmur may be loudest in 1st Right ICS. It isn't associated with systolic
Q. Explain about Gastric ulcers? Gastric ulcers occur in the lesser curvature of the antrum of stomach. A gastric ulcer appears to be caused by reflux of bile and factors that
Explain the Precautions for Use of Light Microscope? 1. Clean the lens system properly. 2. Use xylol only when necessary. 3. Never lower the body tube while looking throu
Name two ways in which the chances of hypothermia can be reduced during outdoor activities. Eating well before going out and wearing warm, wind-proof clothing can reduces the c
Healthy human female X is 25 years old and not pregnant. During the postovulatory phase of X's menstrual cycle, A. there are high blood plasma levels of LH and FSH.
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd