Out of three characters on chromosomes no. 4, two characters indicate linkage and not mentioned by Mendel. These characters were-

Options

A. Pod form - stem length
B. Pod from - pod position
C. Pod from - pod colour
D. Pod postion - stem length

Answer

**Step-by-Step Solution:**

1. **Understand the Context**: The question asks for two characters on chromosome number 4 that indicate linkage and were not mentioned by Mendel. Mendel studied various traits in pea plants, focusing on how they are inherited.

2. **Identify Mendel's Seven Characters**: Mendel studied seven characters in pea plants, which are:
- Flower color
- Flower position (apical or terminal)
- Stem height
- Seed color
- Seed shape (round or constricted)
- Pod shape
- Pod color

3. **Focus on Chromosome Number 4**: The question specifies chromosome number 4. It is important to identify which genes are located on this chromosome.

4. **Identify the Genes on Chromosome 4**: According to the information provided, chromosome number 4 contains three genes:
- Gene for plant height
- Gene for pod shape
- Gene for flower position

5. **Determine Linkage**: Linkage refers to genes that are located close to each other on the same chromosome and tend to be inherited together. In this case, the genes for plant height and pod shape are very close to each other, indicating that they show linkage.

6. **Conclusion**: The two characters that indicate linkage on chromosome number 4 and were not mentioned by Mendel are:
- Plant height
- Pod shape

**Final Answer**: The characters are **plant height and pod shape**.

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