When at hetorozygous tal pea plant of `F_(1)` generation upon self fertilization produces tall and dwarf phenotypes it proves the principle of :-

Options

A. Dominance
B. Segregation
C. Independent assortement
D. Inheritance & purity of gametes

Answer

To solve the question regarding the principle demonstrated by a heterozygous tall pea plant of the F1 generation that produces both tall and dwarf phenotypes upon self-fertilization, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Phenotypes**:
- In pea plants, the tall phenotype (T) is dominant over the dwarf phenotype (t). A heterozygous tall pea plant has the genotype Tt.

2. **Self-Fertilization of Heterozygous Plant**:
- When a heterozygous tall pea plant (Tt) self-fertilizes, the possible gametes produced are T and t.

3. **Punnett Square Analysis**:
- Construct a Punnett square to visualize the offspring:
```
T | t
-----------------
T | TT | Tt
-----------------
t | Tt | tt
```
- The resulting genotypes from this cross are:
- 1 TT (homozygous tall)
- 2 Tt (heterozygous tall)
- 1 tt (homozygous dwarf)

4. **Phenotypic Ratio**:
- The phenotypic ratio of the offspring is 3 tall (TT and Tt) to 1 dwarf (tt). This indicates that both tall and dwarf phenotypes are produced.

5. **Principle of Segregation**:
- The occurrence of both phenotypes (tall and dwarf) in the offspring demonstrates the principle of segregation. This principle states that during gamete formation, the alleles for a trait segregate from each other so that each gamete carries only one allele for each gene.

6. **Conclusion**:
- Therefore, the self-fertilization of a heterozygous tall pea plant producing both tall and dwarf phenotypes proves the principle of segregation.

### Final Answer:
The principle demonstrated is the **Principle of Segregation**.

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