Variations appear during meiosis due to
1 . Independent assortment
2. Crossing over
3. Linkage
4. Glycolysis
Select the correct code

Options

A. Independent assortment
B. Crossing over
C. Both A and B
D. Linkagess

Answer

To determine the reasons for variations during meiosis, we need to analyze each of the provided options:

1. **Independent Assortment**: This principle, derived from Mendel's laws of inheritance, states that genes located on different chromosomes segregate independently during gamete formation. This means that the combination of alleles in the offspring can vary, leading to genetic diversity. Therefore, independent assortment contributes to variations during meiosis.

2. **Crossing Over**: This process occurs during prophase I of meiosis, where homologous chromosomes exchange segments of genetic material. This recombination of genes results in new allele combinations in the gametes, contributing significantly to genetic variation. Thus, crossing over is also a key factor in generating variations during meiosis.

3. **Linkage**: Linkage refers to the tendency of certain genes to be inherited together because they are located close to each other on the same chromosome. This phenomenon does not contribute to genetic variation since linked genes do not assort independently; they tend to be passed on together without recombination. Therefore, linkage does not cause variations.

4. **Glycolysis**: This is a biochemical pathway that breaks down glucose into pyruvate, and it is unrelated to the process of meiosis or genetic variation. Hence, glycolysis does not contribute to variations during meiosis.

Based on the analysis above, the correct options that contribute to variations during meiosis are:

**Correct Code**: 1 (Independent Assortment) and 2 (Crossing Over).

### Final Answer:
The correct options are 1 and 2.

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