Total fertility rate, Biology

Assignment Help:

Total Fertility Rate

Total fertility rate (TFR) is the total number of children a women can be expected to bear in a given population if birth rates are constant for at least one generation. Replacement level is a value of TFR and is the number of children a couple must have to replace themselves. You might think that two parents would have to have only two children to replace themselves.

The actual average replacement level is, however, slightly higher, primarily because some children die before reaching their reproductive years. In developed countries the replacement level is fixed at 2.1. In developing countries where infant mortality rates are high and life expectancies are short, replacement level is about 2.7. If replacement level is low-below 2 i.e. each couple has children less than those required to replace themselves, then the population will actually decline as in the case of Sweden and Germany.


Related Discussions:- Total fertility rate

What are the phospholipids, Q. What are the phospholipids? Phospholipid...

Q. What are the phospholipids? Phospholipids are molecules made of glycerol bound to one phosphate group and to two long molecules of fatty acids. hence, phospholipids are amph

Does ph affect the enzyme activity, Does pH affect the enzyme activity? ...

Does pH affect the enzyme activity? The concentration of hydrogen ions in solution affects the enzyme activity. Every enzyme has maximal efficiency under an optimum pH. As p

Respiration, difference between the respiration occurs in lower and higher ...

difference between the respiration occurs in lower and higher organisms

Formation of identical twins and fraternal twins, Describe the events whic...

Describe the events which lead to the formation of (a) identical twins, (b) fraternal twins.   (a) Identical twins are derived from the products of a one zygote which separa

Explain congenital heart disease (chd), Explain Congenital Heart Disease (C...

Explain Congenital Heart Disease (CHD)? Congenital heart disease is an abnormality at birth in cardiac circulatory structure or function. Optimal management of CHD aims not mer

Explain ketogenic diet, Explan Ketogenic diet Ketogenic diet:   It is ...

Explan Ketogenic diet Ketogenic diet:   It is occasionally used to facilitate the control of epilepsy. Here, the patient  is  initially  fasted  for  48 hours and thereafter,

Anti lipid drugs-peri operative problems, Anti Lipid Drugs :  The current ...

Anti Lipid Drugs :  The current thinking is that it is very important to keep lipid levels low. It helps in preventing atherosclerotic changes in venous grafts and the long-term p

Symmetry, How we explain intenal organs when we talk about symmetry??Is the...

How we explain intenal organs when we talk about symmetry??Is there any animal that is completely symmetric even insid the body?

What would happen to the neuron, If neurons are exposed to a chemical agent...

If neurons are exposed to a chemical agent that prevents the NA+ channels from opening, what would happen to the neuron? What would happen if the K+ channels were inhibited? What d

What do you mean by cephalopods and vertebrates, Q. How does photosensitivi...

Q. How does photosensitivity in annelids, cnidarians and worms differ from insects, cephalopods and vertebrates? In the first mentioned group of animals there are photoreceptor

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