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

Why photosynthetic prokaryotes appeared before more, Why is it more probabl...

Why is it more probable that the photosynthetic prokaryotes appeared before the aerobic eukaryotes? It is more feasible that photosynthetic prokaryotes appeared before the aero

What is the meaning of trocophore, What is the meaning of Trocophore? T...

What is the meaning of Trocophore? This free-swimming ciliated larval stage is found in numerous animal phyla including Mollusca and Annelida. Larvae has a unique circle of pre

How the molecule would increase in mass slightly, Suppose many of the atoms...

Suppose many of the atoms of nitrogen in a double-stranded molecule of DNA, of isotope N-14, were replaced with the isotope N-15. What afffect would this have? a) The nitrogeneo

Determine environmental factors of viscosity and plasticity, Environmental ...

Environmental factors of viscosity and plasticity a) Temperature affects the viscosity of a colloid. Generally, its viscosity decreases as the temperature increases. For e.g.

Nursing assessment of acute glomerulonephritis, Nursing Assessment   Du...

Nursing Assessment   During assessment the child's parents will give you history of upper respiratory infection or skin infection  in the previous one to three weeks. Initially

Explain spoilage of sweetened condensed milk, Q. Explain Spoilage of Sweete...

Q. Explain Spoilage of Sweetened condensed milk? The sweetened condensed milk contains about 8% milk fat, 23% total milk solids and sweetened with the addition of a sweetener,

Which are plant tissues that cover the stem and the leaves, Which are plant...

Which are plant tissues that cover the stem and the leaves? The stem perhaps covered by epidermis (having stomata, cuticle and photosynthetic cells) as in monocots or, alternat

Explain the hydrophobic grid membrane filter (hgmf), Explain the Hydrophobi...

Explain the Hydrophobic Grid Membrane Filter (HGMF)? It is also used to enumerate microorganisms from a variety of food samples. By using this method, organisms as few as 10 ce

What is the cellular structure to which mrna molecules bind, What is the ce...

What is the cellular structure to which mRNA molecules bind to start the protein synthesis? To make proteins mRNA molecules of necessity associate to ribosomes. Ribosomes have

What event marks the beginning of the menstrual cycle, Q. What event marks ...

Q. What event marks the beginning of the menstrual cycle? What is the blood concentration of FSH, LH, estrogen and progesterone in this phase of the cycle? By convention the me

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