Mitosis and Meiosis Quiz
Questions: 16 · 10 minutes
1. A homologous chromosome pair fails to separate during meiosis I, but meiosis II proceeds normally. What is the expected result?
Two gametes are normal, while the other two have an abnormal chromosome number
All four gametes have an abnormal chromosome number for that chromosome
All four gametes are diploid rather than haploid
Only one gamete receives an extra copy, while the other three are normal
2. During which stage does crossing over normally occur between paired homologous chromosomes?
Prophase of mitosis
Metaphase II of meiosis
Prophase I of meiosis
Telophase I of meiosis
3. A human diploid germ-cell precursor contains 46 chromosomes. If meiosis proceeds normally, how many chromosomes will each resulting gamete contain?
23, because meiosis reduces the chromosome number by half
46, because chromosome number is preserved during both divisions
92, because DNA is copied before meiosis begins
12, because the chromosome number is halved during each meiotic division
4. One skin cell completes mitosis under normal conditions. How should the chromosome content of its two daughter cells compare?
Each daughter should have half as many chromosomes as the parent cell
The daughters should have the same chromosome number and nearly the same genetic information
Each daughter should contain a new combination created by crossing over
One daughter should receive maternal chromosomes and the other paternal chromosomes
5. What is the primary role of mitosis in a multicellular organism?
Reducing the chromosome number by half in every body cell
Producing haploid cells for sexual reproduction
Pairing homologous chromosomes to exchange DNA
Producing genetically similar cells for growth, maintenance, and repair
6. How does independent assortment contribute to genetic variation during meiosis?
It copies each chromosome with a different DNA sequence
Sister chromatids exchange entire centromeres during meiosis II
Homologous pairs orient independently at metaphase I, producing different chromosome combinations in gametes
It ensures that every gamete receives only chromosomes inherited from one grandparent
7. Which statement best describes a pair of homologous chromosomes in a diploid cell?
They are two identical copies created during DNA replication
They carry the same kinds of genes at corresponding loci but may contain different alleles
They are sister chromatids joined at a shared centromere
They are chromosomes that carry completely different sets of genes
8. Which event is shared by meiosis II and a typical mitotic division?
Sister chromatids separate and move toward opposite poles
Homologous chromosomes pair to form tetrads
Crossing over occurs between homologous chromosomes
The chromosome number is reduced when homologous pairs separate
9. A researcher examines actively growing root-tip tissue to observe chromosomes moving into two genetically similar nuclei. Which process should the researcher look for?
Fertilization, because it combines two haploid nuclei
Mitosis, because root growth requires additional somatic cells
Meiosis II, because it produces gametes for root growth
Meiosis I, because it separates homologous chromosomes
10. Starting with one diploid parent cell, what is the usual final outcome of meiosis?
Two diploid cells with matching chromosome sets
Four diploid cells that are genetically identical
Four haploid cells, often genetically different from one another
Two haploid cells containing identical chromosome combinations
11. When is nuclear DNA normally replicated in preparation for mitosis or meiosis?
During prophase, after chromosomes condense
During cytokinesis, as the cytoplasm divides
During anaphase, as chromosomes move apart
During S phase of interphase, before division begins
12. A chemical prevents spindle microtubules from attaching properly to chromosome kinetochores. What is the most direct expected effect on mitosis?
DNA replication begins again before chromosomes can condense
Homologous chromosomes cross over more frequently
Cytokinesis produces four haploid cells instead of two diploid cells
Chromosomes cannot be reliably aligned and separated into daughter cells
13. A diploid cell has 2n = 8. Immediately after meiosis I, what does each daughter cell normally contain?
Four chromosomes, each still consisting of two sister chromatids
Eight chromosomes, each still consisting of two sister chromatids
Eight chromosomes, each consisting of one chromatid
Four chromosomes, each consisting of one chromatid
14. What normally happens to sister chromatids during anaphase of mitosis?
They pair with their homologous chromosomes and cross over
They remain joined while homologous chromosomes move apart
They replicate to form two additional copies of each chromosome
Their centromeres separate, and the chromatids move toward opposite poles
15. Cells at the edge of a skin wound divide to replace damaged tissue. Which process is chiefly responsible?
Mitosis, because it produces new somatic cells with the same chromosome number
Meiosis I, because homologous chromosomes must separate before repair
Meiosis II, because sister chromatids must form haploid cells
Fertilization, because two chromosome sets are needed in each replacement cell
16. A student compares metaphase of mitosis with metaphase I of meiosis. Which observation correctly distinguishes metaphase I?
DNA is replicated while chromosomes occupy the cell equator
Sister chromatids have already separated into different cells
Homologous chromosome pairs align together at the cell equator
Chromosomes uncoil and new nuclear envelopes form