Question

Practice Quiz
Multiple Choice:
1. Mitosis results in:
A. Four different cells
B. Two identical cells
C. Four identical cells
D. One haploid cell
2. Meiosis produces:
A. Body cells
B. Somatic cells
C. Gametes
D. Bone cells
3. Haploid cells contain:
A. Double the chromosomes
B. Half the chromosomes
C. No chromosomes
D. Identical chromosomes
4. Genetic variation is created during:
A. Mitosis
B. Meiosis
C. Cytokinesis
D. DNA replication

Short Answer:
1. Explain one difference between mitosis and meiosis.
2. Why does fertilization restore the diploid number?
3. Describe how crossing over increases variation.

Answer 1

Multiple Choice — answers:
1. B
2. C
3. B
4. B

Short Answer:
1. One difference: Mitosis produces two genetically identical diploid somatic cells via one division, while meiosis has two divisions and produces up to four genetically different haploid gametes.

2. Fertilization restores the diploid number because two haploid gametes (each with one set of chromosomes, n) fuse; their chromosome sets add together (n + n), returning the cell to two sets (2n).

3. Crossing over (during prophase I of meiosis) swaps corresponding segments between homologous chromosomes, creating new combinations of alleles on each chromosome. This recombination produces gametes with novel genetic mixes, increasing variation in offspring.