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

Cellular features of the beings of the plant kingdom, Q. What are the major...

Q. What are the major cellular features of the beings of the plant kingdom? The typical plant cells are eukaryotic (have nucleus), photosynthetic (use light to make food) and a

Origin and evolution of metazoa, Origin and Evolution of Metazoa Most ...

Origin and Evolution of Metazoa Most of the early metazoans were soft bodied and so their fossils are rare. The extremely fragmented fossil record does not shed any specific l

How have brain-imaging methods such as pet and mri, How have brain-imaging ...

How have brain-imaging methods such as PET and MRI affected neuroscience research and clinical care? Techniques which capture pictures of the living human brain at work have be

Pvcs during recovery, As the heart rapidly slows during recovery from exerc...

As the heart rapidly slows during recovery from exercise, PVCs commonly occur and usually have no clinical significance. This may be a time when metabolic adjustments in the heart

Population density - biological stress, Population Density - Biological Str...

Population Density - Biological Stress You are aware of what might follow an uncontrolled growth of human population. There will be competition for common consumables and for

What is ionic bonds, What is Ionic bonds ? Ionic Bonds :  Ionic bonds...

What is Ionic bonds ? Ionic Bonds :  Ionic bonds hold atoms together in crystals. They form when oppositely charged atoms, or ions, join (opposite charges attract) to equaliz

Candidiasis, Candidiasis Candidiasis (Moniliasis) is a disease of man, ...

Candidiasis Candidiasis (Moniliasis) is a disease of man, animals and birds and is caused chiefly by Candida albicans. Crop mycosis (thrush) of poultry is caused by C. albicans

Describe organs of female reproductive system, Q. What are the organs that ...

Q. What are the organs that are part of the female reproductive system? The organs that constitute the female reproductive system are the ovaries, the uterus, the Fallopian tub

Theory of epigenesis - pre-mendelian theory, Theor y of Epigenesis (i)...

Theor y of Epigenesis (i)          It was proposed by C.F. Wolff & supported by Von Baer. (ii)         Wolff proposed that germ cells contain definite but undifferentiated

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