An organism is diploid when its cells carry which of the following?

• A. No chromosomes
• B. Two sets of chromosomes
• C. One set of chromosomes
• D. Three sets of chromosomes

Answer: (B)

Verified step by step guidance

1. Understand the concept of ploidy: Ploidy refers to the number of sets of chromosomes in a cell. Diploid organisms have two sets of chromosomes, one set inherited from each parent.
2. Identify the characteristics of diploid cells: In diploid cells, chromosomes are present in pairs. Each pair consists of one chromosome from the mother and one from the father.
3. Compare the options given: Evaluate each option based on the definition of diploid. 'No chromosomes' is incorrect as all living organisms have chromosomes. 'One set of chromosomes' refers to haploid cells, typically found in gametes. 'Three sets of chromosomes' would be triploid, not diploid.
4. Select the correct option: Based on the definition and comparison, the correct answer is 'Two sets of chromosomes', which matches the characteristic of diploid cells.
5. Review the concept: Reinforce the understanding that diploid cells are typical in somatic cells of organisms, allowing for genetic diversity through sexual reproduction.