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

Describe in detail about the chlorophyll molecule, Describe in detail about...

Describe in detail about the chlorophyll molecule Each chlorophyll molecule contains magnesium ion, there could be no green plants without magnesium. As magnesium is present in

Nucleic acid amplification, Ask Prepare a 2-4 page summary of nucleic aci...

Ask Prepare a 2-4 page summary of nucleic acid amplification techniques that are being explored in the development of nucleic assays for clinical use. Research and identify a mo

Drugs derived from plants, A large number of important drugs are derived fr...

A large number of important drugs are derived from plants. For example Tubocuranin, derived from plant-based curare, is used as a muscle relaxant during surgery. Curianol, a Guy

Modification of mitosis, MODIFICATION OF MITOSIS 1 .      CRYPTOMITOS...

MODIFICATION OF MITOSIS 1 .      CRYPTOMITOSIS OR PROMITOSIS : Primitive type of mitosis. In this mitosis nuclear membrane not disappear (remain intact throughout the div

Renal failure and transplantation, KIDNE Y (RENAL FAILURE) - RF - Part...

KIDNE Y (RENAL FAILURE) - RF - Partial or total inability of kidney to carry excretory functions is called RF. It leads to uremia (excess of urea in blood), salt-water imba

What is the plasma membrane of the cell, What is the plasma membrane of the...

What is the plasma membrane of the cell? What are its main functions? The plasma membrane is the outer membrane of the cell; it delimits the cell itself and a cell interior wit

Define tracheal system in details., Define tracheal system in details. ...

Define tracheal system in details. Respiratory system found in insects and some spiders where air passes directly to the tissues through a series of tubules. Since oxygen tran

Interior of the ventricles - heart, Each ventricle has an inflow part begin...

Each ventricle has an inflow part beginning just in front of the corresponding atrioventricular orifice and running forwards to the left towards the apex of the heart. The cavity t

Why c4 plants are more efficient in photosynthesis, C4 plants are more effi...

C4 plants are more efficient in photosynthesis than C3 plants due to: 1. Higher leaf area 2. Presence of larger number of chloroplasts in the leaf cells 3. Presence of thi

What is transgenesis - molecular biology, Molecular Biology - transgenesis ...

Molecular Biology - transgenesis Difficult to successfully insert the gene then successfully re-implant embryo possible pleiotropic effects low success rate / tak

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