Differentiate between a test cross and a reciprocal cross.

Explanation

### Step-by-Step Text Solution:

1. **Definition of Test Cross**: A test cross is a breeding experiment used to determine the genotype of an organism that exhibits a dominant phenotype. This is done by crossing the organism with a homozygous recessive individual. The offspring's phenotypes will reveal the genotype of the dominant organism.

2. **Purpose of Test Cross**: The primary purpose of a test cross is to identify whether the dominant phenotype is due to a homozygous dominant genotype or a heterozygous genotype. If the offspring show a mix of phenotypes (both dominant and recessive), the organism is heterozygous. If all offspring show the dominant phenotype, the organism is homozygous dominant.

3. **Example of Test Cross**: For instance, if a tall plant (which can be either homozygous tall or heterozygous tall) is crossed with a dwarf plant (homozygous recessive), the resulting offspring will help determine the genotype of the tall plant. If the offspring are 50% tall and 50% dwarf, the tall plant is heterozygous. If all offspring are tall, the tall plant is homozygous.

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