Morgan coined the terms

Options

A. linkage and recombination
B. gene and allele
C. X body and linkage
D. homozygous and heterozygous

Answer

To answer the question "Morgan coined the terms," we will analyze each of the given options step by step.

### Step 1: Analyze the first option - Linkage and Recombination
- T.H. Morgan is known for his work in genetics and specifically for the concepts of linkage and recombination. Linkage refers to the tendency of genes located close to each other on a chromosome to be inherited together, while recombination refers to the process by which genetic material is physically mixed during meiosis, leading to new combinations of alleles.
- **Conclusion**: This option is correct as both terms were indeed coined by T.H. Morgan.

### Step 2: Analyze the second option - Gene and Allele
- The term "gene" was coined by the scientist William Johannsen, while "allele," which refers to the different forms of a gene, was coined by William Bateson.
- **Conclusion**: This option is incorrect as neither term was coined by Morgan.

### Step 3: Analyze the third option - X body and Linkage
- The term "X body" was first noted by a scientist named Henking, who described it in relation to the X chromosome. Linkage, as previously mentioned, was coined by T.H. Morgan.
- **Conclusion**: This option is partially correct (linkage is correct), but since X body was not coined by Morgan, this option is incorrect overall.

### Step 4: Analyze the fourth option - Homozygous and Heterozygous
- The terms "homozygous" and "heterozygous" were also coined by William Bateson. Homozygous refers to having two identical alleles for a particular gene, while heterozygous refers to having two different alleles.
- **Conclusion**: This option is incorrect as these terms were not coined by Morgan.

### Final Answer
Based on the analysis of all the options, the correct answer to the question "Morgan coined the terms" is:
**Linkage and Recombination.**

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