Question

According to Mendel's first law the monohybrid phenotypic ratio is

• A. 3:1
• B. 4:1
• C. 1:1
• D. 1:2:1

Answer 1

The Correct Option is A

To solve the problem, we need to identify the phenotypic ratio according to Mendel's first law for a monohybrid cross.

1. Understanding Mendel's First Law:
Mendel's First Law is the Law of Segregation, which states that during the formation of gametes, the two alleles for a trait separate so that each gamete carries only one allele.

2. Monohybrid Cross:
A monohybrid cross involves a single pair of contrasting traits (e.g., tall vs. short in pea plants).
The typical cross is between two heterozygous individuals (Tt × Tt), which gives: - TT (tall) - Tt (tall) - Tt (tall) - tt (short)

3. Phenotypic Ratio:
- 3 tall : 1 short
So, the phenotypic ratio is 3:1

Final Answer:
The monohybrid phenotypic ratio is $ 3 : 1 $.