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 transposable elements, Transposable elements are able to move ...

Transposable elements are able to move around the genome by precise or imprecise excision events. What is meant by imprecise excision? A. Imprecise excision refers to a transpo

Define the parathryroid gland, Which of the following serves as an effector...

Which of the following serves as an effector, or part of an effector, that functions in a negative feedback system? A. 1,25-dihydroxyvitamin D Receptors located intracellularly

How are grasslands classified, How are grasslands classified? Grasslan...

How are grasslands classified? Grasslands might be classified into steppes and savannahs. In the steppes the prevailing vegetation is grass, as in the pampas of South America

Find if the sugar is a d- or l- stereoisomer, If carbon 1 is the carbonyl g...

If carbon 1 is the carbonyl group of a 6-carbon aldose (aldohexose), which carbon determines if the sugar is a D- or L- stereoisomer? Select one: a. 1 b. 2 c. 3 d. 4

Nervous tissue and its components, NE R V OU S TISSUE The nervous...

NE R V OU S TISSUE The nervous tissue in general develops from the ectoderm of the embryo, but the microgliocytes. It does not have a matrix. The special properti

Membrane that selects based on pore size, A transport process in which phys...

A transport process in which physical (hydrostatic) pressure drives part of a fluid through a membrane that selects based on pore size

Which cell count elevates in case of allergy or plastic worm, Which cell co...

Which cell count is likely to be elevated when an individual has an allergy or parasitic worms? a) Red blood cells b) Erythrocyte c) Eosinophil (pron: e-o-sin-o-fill)

What is the significance of choanocyte, What is the significance of Choanoc...

What is the significance of Choanocyte? Unique collar-shaped cells whose flagella are responsible for generating water current in the sponge. As flagella beats, food particles

External sources for health care, Normal 0 false false fals...

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

Phylum and chordata, phylum and chordata ex. and their classiication

phylum and chordata ex. and their classiication

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