How many chromosomes will be in a gamete if the normal cell has four chromosomes?

Analyze the question: A normal body (somatic) cell has 4 chromosomes. This is the diploid number (2n = 4). We need the number of chromosomes in a gamete (sex cell).

Concept: Gametes (sperm and egg cells) are formed by meiosis, a reduction division. Meiosis halves the chromosome number, so gametes are haploid (n). This ensures that when two gametes fuse during fertilization, the zygote restores the diploid number.

Solution:

• Diploid number: 2n = 4
• Haploid number: n = 4 ÷ 2 = 2

Check: Gamete (2) + gamete (2) → zygote (4). This matches the normal cell's chromosome number, so the answer is consistent.

Why the other options are wrong:

• B (4): This is the diploid number, which is found in body cells, not gametes.
• C (6) and D (8): These would be more than the parent cell has, which is impossible in meiosis. 8 would be the chromosome count after DNA replication in some contexts, but not in a gamete.

Exam tip: Remember "Gametes are Half." Whenever a question asks about the number of chromosomes in a gamete, just divide the body cell number by 2. For a zygote or body cell, keep the full number (diploid). In humans: body cell = 46, gamete = 23.