Homozygous and weterozygous, Biology

Assignment Help:

Homozygous and Weterozygous

In an individual two identical alleles may exist [or a given character and, hence, the individual is referred to as Homozygous (e.g. AA and aa). If there are two non-identical or different alleles for a given character, the indivitlual is reffered to as heterozygous (e.g. Aa).

Let us examine a situation where both the parents arc homozygous. The male is homozygous recessive aa, and female is homozygous dominant AA. During nlciosis in the male the two 'a' alleles separate from each other so lhat cach spcrln has only a
single 'a' allele. Similarly, in the female parent each egg has one 'A' allelc. 'I'hc fertilisation of the 'A' egg by 'a' sperm results in n hcterozygoiis atiimal with 'Aa'. The form of gene which occurs in an individual in nalure is called the 'wild type' while a 'mutant type' is the one in which the genetic material is somcwhat altered. Mutants arise due to various reasons.

The alleles which express themselves in both honiozygous and heterozygous conditions are known as the dominant alleles. For example, 1T represents tallricss (homoqgous). The individuals having the alleles TT, and Tt would be tall as T is a dominant allele and it can express itself in both homozygous and heterozygous conditions. Some alleles express themselves only in hornozygous condition ant1 arc rcfcrrcd to as recessive alleles. In the height characteristic, dwarfness can be seen in individuals that have the alleles 'tt', i.e., recessive allelus are expresscti in homozygous condition only.


Related Discussions:- Homozygous and weterozygous

Explain the meaning of life style modification, Explain the Meaning of Life...

Explain the Meaning of Life Style Modification Life Style Modification (LSM) is an important aspect in the treatment of diabetes. LSM will help the people who are pre-diabetic

Blood pressure, An adequate level of pressure is needed in the arteries to ...

An adequate level of pressure is needed in the arteries to keep the blood flowing through the cardiovascular system. The chief determinant of arterial pressure is the volume of blo

How different is the amphibian heart from the fish heart, How different is ...

How different is the amphibian heart from the fish heart? The fish heart has only two chambers, a ventricle and an atrium, and the blood that comes to it is purely venous. I

Determine the synaptic process, Since neurotransmitters are not consumed in...

Since neurotransmitters are not consumed in the synaptic process, what are the mechanisms to decrease their concentrations in the synaptic cleft after they have been used? As t

How genes can be exchanged between chromatids, Q. How Genes can be exchange...

Q. How Genes can be exchanged between chromatids? When two homologous chromosomes physically exchangecorresponding segments during prophase I of meiosis, geneticists call it cr

What are the cytoplasmic structures present in animal cells, Q. What are th...

Q. What are the main cytoplasmic structures present in animal cells? The main cytoplasmic structures of the cell are the centrioles, the cytoskeleton, mitochondria, peroxisomes

State in brief about the macronutrients, State  in brief about the Macronut...

State  in brief about the Macronutrients  Each element is specific in its function in plant metabolism, however, the exact functions for a number of them are still not known. T

What are plankton and benthos, What are plankton, nekton and benthos? P...

What are plankton, nekton and benthos? Plankton, nekton and benthos are the three groups into which aquatic living beings may be separated. The plankton is formed by the alg

Explain six different genotypes, ABO blood groups in humans are controlled ...

ABO blood groups in humans are controlled by the gene I. It has three alleles - IA, IB and i. As there are three dissimilar alleles, six different genotypes are possible. How many

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