When chiasma frequency is 100%, the percentage of crossing over is
A. 50%
B. 100%
C. 150%
D. 75%
Answer: Option A
Solution (By Examveda Team)
When chiasma frequency is 100%, the percentage of crossing over is 50%.A chiasma is the point of contact, the physical link, between two chromatids belonging to homologous chromosomes. At a given chiasma, an exchange of genetic material can occur between both chromatids and is called a chromosomal crossover.
When chiasma is organized in between two gene loci, only 50% of meiotic products shall be crossovers and 50% non-crossovers. Thus, the chiasma frequency is twice the frequency of cross-over products, therefore, when the chiasma frequency is 100%, the percentage of crossing-over is halved i.e. 50%.
Related Questions on Genetics and Plant Breeding
Genetic code was discovered by
A. Khorana and Methaei
B. Flemming and Methaei
C. Holley, Nirenberg and Khorana
D. Holley and Nirenberg
Progeny of breeder seed is referred to as
A. Breeder seed
B. Nucleus seed
C. Foundation seed
D. Certified seed
Molecular basis of organ differentiation depends on the modulation in transcription by
A. RNA pol
B. Transcription factor
C. Anticodon
D. All of the above
The phenomenon of linkage was first observed by
A. Bateson and Punnet
B. Nilson
C. Hugo de Vries
D. Mendel

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