Homozygous and weterozygous, Biology

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.

Posted Date: 12/11/2012 3:16:49 AM | Location : United States







Related Discussions:- Homozygous and weterozygous, Assignment Help, Ask Question on Homozygous and weterozygous, Get Answer, Expert's Help, Homozygous and weterozygous Discussions

Write discussion on Homozygous and weterozygous
Your posts are moderated
Related Questions
State the prevention of Campylobacteriosis Prevention: the various ways to prevent campylobacteriosis are: Wash hands before preparing foods. Wash hands immediatel

Q. What are the secondary and the primary constrictions of a chromosome? And what is the other name given to the secondary constriction? Primary constriction is the narrower re

Types of individuals in Cnidaria There are two forms of individuals in Cnidaria: Polyp Medusa Polyp is tubular, the oral end being free carrying

While  various  positive  control  components  lie  close  to the  gene  they  regulate additional can be situated long distances away (sometimes 10-50 kb) either upstream or downs

Q. What is Phenylketonuria? The essential amino acid phenylketonuria is utilized for tissue protein synthesis and hydroxylated to form tyrosine. The hydroxylation reaction requ

Determine the Modification of native starch Modification of native starch can be either physical or chemical. Chemical modification includes reaction of starch with  acid or al

Micro-organisms: The micro-organisms mixed up in aerobic absorption and their activities are the same as those found in nature. The organic compounds are oxidised to H

Explain about the Obliques muscles The superior and inferior oblique muscles form an angle of about 51 0 with the optical axis. The oblique muscles produce cyclorotation becau

Protein X has an absorptivity of 0.4 mL . mg -1 . cm-1 at 280nm. What is the ab sorbance at 280 nm of a 2.0 mg. mL-1 solutionof protein X ? (Assume the light path is 1 cm).

What is Fluorescent Microscope? In above said microscopes, image is produced from light that passes through a specimen. In fluorescent microscope, however, specimen image is f