What is crossing over?how meiosis related to this phenomenon, Biology

Assignment Help:

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

The 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 kind of linkage is called as complete linkage. In the first division of meiosis (meiosis I) though the crossing over phenomenon may occur. The Chromosomes from a pair of homologous may exchange extremities and some once linked alleles, for instance, A-b and a-B, recombine to form different gametes, in the case, A-B and a-b.

The Crossing over may happen when the arms of the chromatids of each homologous are paired during meiosis. The Matching portions of the extremities of two nonsister chromatids (one from one homologous of the pair) break and the pieces are exchanged, all 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 formed, instead of A-b and a-B.

(The percentage of the recombinant gametes relating to normal gametes depends upon the crossing over rate that in its turn depends upon how far distant the given alleles are in the chromosome.)

 


Related Discussions:- What is crossing over?how meiosis related to this phenomenon

Features of estuaries, Features of Estuaries The physicochemical prop...

Features of Estuaries The physicochemical properties of the estuaries have large variation in several parameters and this often creates stressful environment for organisms. T

Urine sugar testing, Testing for urine sugars is not recommended for either...

Testing for urine sugars is not recommended for either diagnosis or monitoring of patients with diabetes. This is because a urine sugar is not a reliable test. When no facilities a

Botany, economic importance of viruses and bacteria ?

economic importance of viruses and bacteria ?

Determine the phospholipids of the membrane, Determine the phospholipids of...

Determine the phospholipids of the membrane The phospholipids of the membrane are arranged in a bilayer with their polar head groups on the exterior and the nonpolar hydrophobi

Gorgonids, Gorgonids yield chemicals like prostaglandins, medically useful ...

Gorgonids yield chemicals like prostaglandins, medically useful for birth control, prevention of peptic ulcers, treatment of asthma, regulation of blood pressure, etc. Sponges are

Craninal nerves, Craninal nerves: Cranial nerves take their origin f...

Craninal nerves: Cranial nerves take their origin from different areas of brain  Some of them are sensory, some are motor and a few are mixed nerves. There are 12 pair

Define iron - the micronutrient, Define Iron - The Micronutrient Iron, ...

Define Iron - The Micronutrient Iron, as you may be aware, is a trace element present in the body. The body contains approximately 3 - 3.5 g of iron of which about two thirds i

Neurological symptoms and signs, Neurological symptoms and signs occur in 3...

Neurological symptoms and signs occur in 30 to 40 per cent of patients with IE, are more frequent when IE is caused by S. aureus, and are associated with increased mortality rates.

Ketosis, K e to s i s It is also known as acetonemia in bovines or...

K e to s i s It is also known as acetonemia in bovines or pregnancy toxaemia in sheep and is associated with ketonemia, ketonuria and low blood glucose. E t iol

Determine the osseointegration, What is osseointegration The smaller th...

What is osseointegration The smaller the devital zone that forms around the implant subsequent to the surgical trauma, the more likely rigid fixation will occur. The aim is to

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