Which postulate of Mendel is still universal in nature ?

Options

A. Postulate I
B. Postulate II
C. Postulate III
D. Postulate IV

Answer

**Step-by-Step Solution:**

1. **Understanding Mendel's Contribution**: Gregor Mendel is known as the father of genetics. He conducted experiments on pea plants and formulated four fundamental postulates that describe the inheritance of traits.

2. **Identifying Mendel's Postulates**: The four postulates of Mendel are:
- **Postulate 1**: Law of Paired Factors
- **Postulate 2**: Law of Dominance
- **Postulate 3**: Law of Segregation
- **Postulate 4**: Law of Independent Assortment

3. **Analyzing Each Postulate**:
- **Postulate 1 (Law of Paired Factors)**: This states that traits are controlled by pairs of factors (alleles), but it doesn't specify how these factors segregate during gamete formation.
- **Postulate 2 (Law of Dominance)**: This postulate explains that in a heterozygous condition, one allele can mask the expression of another. However, this is not universally applicable to all traits.
- **Postulate 3 (Law of Segregation)**: This postulate states that during the formation of gametes, the two alleles for a trait segregate from each other so that each gamete carries only one allele for each trait. This is universally applicable as it applies to all sexually reproducing organisms.
- **Postulate 4 (Law of Independent Assortment)**: This states that alleles for different traits assort independently of one another during gamete formation, but this is not true for genes located close to each other on the same chromosome.

4. **Conclusion**: Among the four postulates, the **Law of Segregation (Postulate 3)** is the one that is still considered universal in nature as it applies to all sexually reproducing organisms and is fundamental to the understanding of inheritance.

**Final Answer**: The postulate of Mendel that is still universal in nature is **Postulate 3: Law of Segregation**.

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