Question

A doubled haploid (DH) plant is

• A. Always vigorous
• B. Cent per cent homozygous
• C. Cent per cent heterozygous
• D. Always true breeding in cross pollinated species

Hint:

Doubled haploids (DH):
- Completely homozygous.
- Produced by chromosome doubling of haploids.
- Used in plant breeding to fix traits.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
This question tests knowledge of doubled haploids and their genetic constitution.

Step 2: Detailed Explanation:
A doubled haploid (DH) plant is produced by doubling the chromosome number of a haploid.
It is cent per cent homozygous because it contains two identical sets of chromosomes.
It is not always vigorous (A) - vigour varies.
It is not heterozygous (C) - it is completely homozygous.
It is true breeding in self-pollinated species, but not always in cross-pollinated species (D).
Thus, the correct answer is cent per cent homozygous.

Step 3: Final Answer:
Thus, a doubled haploid plant is cent per cent homozygous, which corresponds to option (B).
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