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 major parts of ferns, Q. What are the major parts of ferns? ...

Q. What are the major parts of ferns? Ferns are constituted by small roots that come downwards from the rhizome stem and often horizontalized. The fronds also arise from the rh

Explain carbon and oxygen aspect of using phase rule, Explain carbon and ox...

Explain carbon and oxygen aspect of using phase rule? Consider a system containing solid carbon (graphite) and a gaseous mixture of O 2 , CO, and CO 2 . There are four species

Types of mode of nutrition, what is the mode of nutrition of fungi,bacteria...

what is the mode of nutrition of fungi,bacteria and man

Define growth and development of infants and preschoolers, Define Growth an...

Define Growth and Development of Infants and Preschoolers? In this unit, we learnt about the various aspects related to the growth and development of infants and preschoolers.

How can the binding of two amino acids, Q. How can the binding of two amino...

Q. How can the binding of two amino acids for the peptide formation be explained? A peptide is formed when a carbon from the carboxyl group of one amino acid is connected to th

Explain heterozygous individual and homozygous individual, What is the ge...

What is the genetic condition in which the heterozygous individual has different phenotype from the homozygous individual? This situation is called lack of dominance and it can

Tolerance range, Maximum and minimum range of an animal with the factors of...

Maximum and minimum range of an animal with the factors of Ph Salinity Pressure Relative human

Explain in brief about the diseases sleep paralysis, Explain in brief about...

Explain in brief about the diseases Sleep paralysis This is an episode of paralysis in the transition between wakefulness and sleep. The period of paralysis is usually brief bu

Tracheal gills - respiration, Tracheal Gills - Respiration In many spe...

Tracheal Gills - Respiration In many species of aquatic insects the air in the trachae is replenished by diffusion of oxygen via tracheal gills. Many aquatic insects carry a t

List the functions of insulin, Q. List the functions of insulin? a) Ins...

Q. List the functions of insulin? a) Insulin controls the level of the sugar (glucose) in the blood. b) Insulin permits cells to use sugar (glucose) for energy. Cells cannot

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