NEET UG 2003 — Zoology Principles of Inheritance and Variation

2003mcqmedium

In Drosophila, the sex is determined by,

Official previous-year question

Held on 30 Apr 2003 · Verified 9 Jul 2026.

Options

A
the ratio of number of X-chromosome to the sets of autosomes
B
$\mathrm{X}$ and $\mathrm{Y}$ chromosomes
C
the ratio of pairs of $\mathrm{X}$ -chromosomes to the pairs of autosomes
D
whether the egg is fertilized or develops parthenogenetically

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Solution

In Drosophila, sex is primarily determined by the $\mathrm{X}: \mathrm{A}$ ratio, or the ratio of the number of $\mathrm{X}$ chromosomes to the number of sets of autosomes not because of the presence of a Y chromosome as in human sex determination. Although the $\mathrm{Y}$ chromosome is entirely heterochromatic, it contains at least 16 genes, many of which are thought to have male-related functions. Related Theory In butterflies, sex is determined by chromosome differences. But unlike in humans with the familiar $X$ and $Y$ , in butterflies, it is the femates that determine the sex of offspring. Males are $\mathrm{ZZ}$ , while females are $\mathrm{ZW}$

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NEET UG 2003 — Zoology Principles of Inheritance and Variation

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NEET UG Principles of Inheritance and Variation in other years

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NEET UG 2003 — Zoology Principles of Inheritance and Variation

Options

Did you get this right?

Solution

Your note

NEET UG Principles of Inheritance and Variation in other years

More NEET UG Principles of Inheritance and Variation questions

Other Zoology topics for NEET UG

Molecular Basis of Inheritance

Biotechnology - Principles and Processes

Human Health and Diseases

Human Reproduction

Evolution

Biotechnology and Its Applications

Keep practicing Principles of Inheritance and Variation