Examples of Complete Linkage
Which of the following is/are example(s) of complete linkage-
- Male drosophila
- Female silk moth & female poultry
- Sex chromosomes of all heterogametic species
- All the above — Correct Answer
Explanation:
Correct Answer: All the above
Complete linkage (zero crossing over) is not universal — it is a property of specific organisms or chromosome regions. All three listed examples are classical instances of complete linkage.
Classical Examples of Complete Linkage
| Example | Details |
|---|---|
| Male Drosophila | Crossing over is entirely suppressed in male fruit flies — all genes on the same chromosome are completely linked |
| Female silk moth (Bombyx mori) | Crossing over is suppressed in females of silk moth |
| Female poultry | Female poultry is heterogametic (ZW); crossing over is suppressed in the heterogametic sex |
| Sex chromosomes of all heterogametic species | The non-homologous regions of sex chromosomes (X/Y in mammals; Z/W in birds) do not recombine |
General Rule
- In species where one sex is heterogametic (XY males in mammals; ZW females in birds), crossing over is often suppressed in that heterogametic sex.
- In male Drosophila specifically, autosomes too show complete linkage — unique among organisms.
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
