Extremes of heat and cold, Biology

Assignment Help:

Extremes of Heat and Cold

Deserts are regions of aridity with rainfall of less than 20 cm per year and the soil, though L, fertile, is too porous to retain any water. In summer there is great diurnal variation in temperature from 40°C during the day to below 15°C the same night. The light intensity reaches higher peak due to lack of cloud cover. The true deserts are Sahara in Africa and Great desert in Australia where the annual rainfall is less than 2 cm. Plants and animals which survive under such conditions have special features that allow them to withstand high temperature and lack of water.

The other extreme of temperature is seen in the arctic and alpine tundras. The word tundra means bare mountain tops in Finnish. Tundras are kozen most of the year round and are very similar to deserts as the rainfall here is also about 20 cm per year. But during the short summers, water is plentiful as the topmost layer of ice melts. The ground gets covered with short grass and patches of moss and lichens. Beneath the thawed layer of 3-5 cm, the soil called permafrost remains permanently frozen. Since the roots cannot penetrate deep in the soil trees do not grow here.


Related Discussions:- Extremes of heat and cold

Explain the advantages of double beam method, Explain the Advantages of Dou...

Explain the Advantages of Double Beam Method? The double beam method has advantage over single beam as it automatically corrects, for the change in light transmission, through

What is an accommodation, What is an accommodation? Accommodation is th...

What is an accommodation? Accommodation is the ability of the eye to focus on an object situated at variable distances from the eye. Like a camera, even the eye requires to cha

Which are the glands present in the epidermis of mammals, Which are the gla...

Which are the glands present in the epidermis of mammals, birds and reptiles? In the epidermis of birds and reptiles there are almost no glands. In mammals there are sweat glan

Define development - terminologies used in chromatography, Define Developme...

Define Development - Terminologies used in Chromatography? Development is the process of passing a mobile phase over the adsorbent or support. During the development the sample

Poultry and duck diseases-avian reovirus infections, Avian reovirus infecti...

Avian reovirus infections There are several avian reoviuses isolated from chicken, turkey and other species of birds. They are associated with arthritis (tenosynovitis), respir

How do sponges try to protect themselves, Q. How do sponges try to protect ...

Q. How do sponges try to protect themselves against harm from the environment? Is that method rudimentary or efficient? Sponges can close their pores to avoid the entrance of w

What do you mean by blackcaps, Q. What do you mean by Blackcaps? Blackc...

Q. What do you mean by Blackcaps? Blackcaps are small songbirds found throughout Europe. A large population of blackcaps inhabits the forests of Germany. These blackcaps have t

Explain about insulin concentrations, Insulin Concentrations The doctor...

Insulin Concentrations The doctor always prescribes insulin dosage in units. Thus all types of insulin (crystalline, NPH, Lente, and so forth) is available in 10-ml vials that

What are hexoses, What are hexoses? What are some examples of hexoses with ...

What are hexoses? What are some examples of hexoses with important biological functions? Hexoses are carbohydrates made of six carbons. Glucose, fructose and galactose are inst

Genetically modified foods-golden rice, Normal 0 false false ...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd