Haploids are able to express both recessive and dominant alleles /mutations because there are :

Options

A. many alleles for each gene
B. two alleles for each gene
C. only one allele for each gene in the individual
D. only one allele in a gene

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Haploids**: Haploids are organisms or cells that contain only one set of chromosomes (N). This means they have only one allele for each gene.

2. **Alleles and Genes**: A gene is a segment of DNA that codes for a specific trait, and it can have different forms known as alleles. For example, for a gene controlling flower color, the alleles could be R (dominant) for red and r (recessive) for white.

3. **Expression of Alleles**: In diploid organisms (2N), individuals have two alleles for each gene (one from each parent). The dominant allele will mask the expression of the recessive allele unless the organism is homozygous recessive (rr).

4. **Haploid Expression**: In haploids, there is only one allele present for each gene. This means that whatever allele is present will be expressed. There is no second allele to mask its expression, which allows both dominant and recessive traits to be expressed if the single allele is recessive.

5. **Conclusion**: Therefore, haploids can express both recessive and dominant alleles because they have only one allele for each gene. This is the key reason why haploids can express traits without the influence of another allele.

6. **Correct Answer**: The correct answer to the question is that haploids express both recessive and dominant alleles because there is only one allele for each gene in an individual.

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