Question

In Mendel’s monohybrid cross of tall vs dwarf plants, the $F_1$ progeny are ___.

• A. Homozygous
• B. Heterozygous
• C. Hemizygous
• D. Either a or b

Answer 1

The correct option is B

Heterozygous

Mendel’s monohybrid cross involves two pure plants, say one tall (TT) and one short (tt). Hence $F_1$ progeny would have been all heterozygous (Tall, say Tt). The tall plant will produce only one type of gamete with the dominant allele (T). Similarly, the dwarf plant will produce only one type of gamete with the recessive allele (t). In the F1 these two gametes will fuse and the offspring will be a heterozygous tall plant (Tt).