Explain about crossing over, Biology

Assignment Help:

What is crossing over? How is meiosis related to this phenomenon?

Linked alleles, for instance, A-b and a-B, form the gametes A-b and a-B that maintain the linkage of the alleles. This type of linkage is known as complete linkage. In the first division of meiosis (meiosis I) however the crossing over phenomenon may happen. Chromosomes from a pair of homologous may exchange extremities and some once linked alleles, for instance, A-b and a-B, recombine to form dissimilar gametes, in the case, A-B and a-b.

Crossing over may occur when the arms of the chromatids of each homologous are paired during meiosis. Matching portions of the extremities of two nonsister chromatids (one from one homologous of the pair) break and the pieces are exchanged, each of them becoming part of the arm of the other chromatid. For instance, if the allele A is situated in a side of the arm relating to the point of breaking and the allele b is located in the other side, they will be separated and gametes A-B and a-b will be produced, instead of A-b and a-B.

 


Related Discussions:- Explain about crossing over

Fermentation, what is steroid production by microbial metabolism

what is steroid production by microbial metabolism

Enema, Enema Enema may be given for the purpose of cleansing, for t...

Enema Enema may be given for the purpose of cleansing, for therapeutic purpose; to relieve intra-cranial pressure, abdominal distension, intusssception and for diagnostic p

Explain total anomalous pulmonary, Explain Total Anomalous pulmonary Venous...

Explain Total Anomalous pulmonary Venous Connection (TAPVC) ? In this congenital anomaly there is no direct communication between the pulmonary veins and the left atrium. All

Where do pga and glycine gain entry, Where do PGA and glycine gain entry re...

Where do PGA and glycine gain entry respectively after being formed during photorespiration in plants? What occurs to them immediately after?

Deficiency diseases-phosphorus deficiency, Phosphorus deficiency Defici...

Phosphorus deficiency Deficiency of phosphorus is usually primary and is widespread under natural conditions. It is characterized by pica, poor growth, infertility, and osteody

Social basis of primitive life, Social Basis of Primitive Life: In th...

Social Basis of Primitive Life: In the previous section, we gave you a glimpse of  how the primitive human beings faced the problems of day to day existence and found some so

Why are the tropical forests also known as stratified forest, Why are the t...

Why are the tropical forests also known as stratified forests? In the tropical forests tall trees of several species have their crowns forming a superior layer under which dive

Define denaturation, Denaturation: With respect to the nucleic acids, refe...

Denaturation: With respect to the nucleic acids, refers to the conversion from the double-stranded to single-stranded state, many times achieved by heating or alkaline conditions.

Biosphere, The biosphere is composed of all living organism. This sphere in...

The biosphere is composed of all living organism. This sphere includes all the microorganism, plants and animals of earth. In fact biosphere involves interaction of living beings w

ASSINMENT, HISTORY ON CLASSIFICATION IN BIOLOGY

HISTORY ON CLASSIFICATION IN BIOLOGY

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