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!
Population Regulation
The number of individuals in a natural population varies with time. If the size of a population declines too drastically due to some reason, it may become extinct, but may later be re-established by immigration from other populations. On the other hand, increase in size of a population is not infinite since the carrying capacity of the environment always imposes a restriction upon it. In spite of such fluctuations, however, an outstanding feature of most large populations is that their average size changes relatively little over the years and certainly less than is expected from their biotic potentials. This indicates that population sizes are regulated in such a way that small population grow fast, larger populations grow more slowly and still larger populations decline.
Let us see what brings about such ecological homeostasis. In low-diversity, physically stressed ecosystems or in those subjected to irregular or unpredictable external perturbations, populations tend to be regulated by physical components such as weather, water, chemical limiting factors, pollution etc. In high diversity ecosystems, or in those which are not physically stressed, populations tend to be biologically controlled. In all ecosystems there is a strong tendency for all populations to evolve through natural selection towards self-regulation such as failure of reproduction and self-inflicted mortality. Even though this is difficult to achieve under external stress. It is because over-population is not in best interests of any population. Thus it can be said that limitation of number in any population is brought about by the action and interaction of two basic regulatory processes namely density dependent and density independent factors. We will discuss these processes in the following subsections.
Explain Changing Body Composition with Ageing? With ageing, a progressive decline in the water content and the lean body mass is accompanied by an increasing proportion of body
What is the uses of PET scans- Brain function PET scans provide colour-coded images of person's brain as they undertake different sorts of task, such as reading words, solving
Normal 0 false false false EN-IN X-NONE X-NONE
Q. Management goals for diverticular disease? The management goals discussed above are basic to prevention of diverticulitis. However, diet therapy during diverticulitis may b
introduction of an assignment about radiation sterilization
Q. What are the major human diseases caused by virus? Among diseases caused by virus are common cold, variola (considered eradicated nowadays), mumps, measles, rubella, AIDS, t
Determine the Cardio-vascular System Cardio-vascular system consists of a heart and blood vessels. The function of cardio- vascular system is to maintain blood supply to all t
Functions of Testis The testis performs the following two functions: Proliferation of spermatozoa and Secretion of steroid hormones
Prevention and control The organism is sensitive to penicillin, tetracycline and other broad-spectrum antibiotics. Newer generation drugs are being used for the treatment of affec
MEIOSIS Every organism is mortal, It becomes old and wornout with advancing age (= ageing ) and ultimately dies ,Before death however ,it reproduces its own kind, so
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