BIO 1201 (Gregg) Exam 3 Questions and Answers|
Updated| Pass Guaranteed| LSU
1. Which statement correctly compares the products of mitosis and
meiosis?
A. Mitosis produces four haploid cells; meiosis produces two diploid cells
B. Both produce two identical diploid cells
C. Both produce four identical haploid cells
D. Mitosis produces two genetically identical diploid cells; meiosis
produces four genetically different haploid cells
Answer: D
Rationale: Mitosis involves one division and maintains chromosome
number for growth and repair. Meiosis involves two divisions and produces
gametes with half the chromosome number.
2. Homologous chromosomes are:
A. A pair of chromosomes, one from each parent, with the same genes
at the same loci, though possibly different alleles
B. Two identical sister chromatids
C. Chromosomes from the same parent
D. Chromosomes that carry different genes
Answer: A
Rationale: Homologs are similar in length, centromere position, and gene
sequence. Alleles for a given gene can differ between them.
BIO 1201 Exam 3 - Page 1
,3. Synapsis occurs during:
A. Metaphase II of meiosis
B. Prophase of mitosis
C. Prophase I of meiosis
D. Anaphase I
Answer: C
Rationale: Homologous chromosomes pair up tightly along their length,
forming a tetrad (bivalent) held by the synaptonemal complex.
4. Crossing over involves:
A. Exchange between sister chromatids
B. Separation of sister chromatids
C. Exchange of segments between nonsister chromatids of homologous
chromosomes during prophase I
D. Duplication of chromosomes
Answer: C
Rationale: Chiasmata are the visible sites of crossing over. Recombinant
chromosomes carry a combination of maternal and paternal alleles.
5. What separates during anaphase I of meiosis?
A. Homologous chromosomes
B. Sister chromatids
C. Nucleotides
D. Centrioles
Answer: A
Rationale: Each chromosome still consists of two sister chromatids that
remain attached at the centromere until anaphase II.
BIO 1201 Exam 3 - Page 2
, 6. Why is meiosis I called the reduction division?
A. The DNA content is doubled
B. The chromatids separate
C. The cells become diploid
D. The chromosome number is halved because homologous pairs
separate
Answer: D
Rationale: After meiosis I, each cell is haploid (n), though each
chromosome still has two chromatids.
7. A human cell with 46 chromosomes undergoes meiosis. How many
chromosomes are in each cell at the end of meiosis II?
A. 46
B. 23
C. 92
D. 12
Answer: B
Rationale: The four daughter cells are haploid with 23 single-chromatid
chromosomes each.
8. Independent assortment occurs during:
A. Prophase II
B. Metaphase I, when tetrads orient randomly at the metaphase plate
C. Telophase II
D. S phase
Answer: B
Rationale: The orientation of each homologous pair is independent of the
others, so maternal and paternal chromosomes are distributed randomly.
BIO 1201 Exam 3 - Page 3
Updated| Pass Guaranteed| LSU
1. Which statement correctly compares the products of mitosis and
meiosis?
A. Mitosis produces four haploid cells; meiosis produces two diploid cells
B. Both produce two identical diploid cells
C. Both produce four identical haploid cells
D. Mitosis produces two genetically identical diploid cells; meiosis
produces four genetically different haploid cells
Answer: D
Rationale: Mitosis involves one division and maintains chromosome
number for growth and repair. Meiosis involves two divisions and produces
gametes with half the chromosome number.
2. Homologous chromosomes are:
A. A pair of chromosomes, one from each parent, with the same genes
at the same loci, though possibly different alleles
B. Two identical sister chromatids
C. Chromosomes from the same parent
D. Chromosomes that carry different genes
Answer: A
Rationale: Homologs are similar in length, centromere position, and gene
sequence. Alleles for a given gene can differ between them.
BIO 1201 Exam 3 - Page 1
,3. Synapsis occurs during:
A. Metaphase II of meiosis
B. Prophase of mitosis
C. Prophase I of meiosis
D. Anaphase I
Answer: C
Rationale: Homologous chromosomes pair up tightly along their length,
forming a tetrad (bivalent) held by the synaptonemal complex.
4. Crossing over involves:
A. Exchange between sister chromatids
B. Separation of sister chromatids
C. Exchange of segments between nonsister chromatids of homologous
chromosomes during prophase I
D. Duplication of chromosomes
Answer: C
Rationale: Chiasmata are the visible sites of crossing over. Recombinant
chromosomes carry a combination of maternal and paternal alleles.
5. What separates during anaphase I of meiosis?
A. Homologous chromosomes
B. Sister chromatids
C. Nucleotides
D. Centrioles
Answer: A
Rationale: Each chromosome still consists of two sister chromatids that
remain attached at the centromere until anaphase II.
BIO 1201 Exam 3 - Page 2
, 6. Why is meiosis I called the reduction division?
A. The DNA content is doubled
B. The chromatids separate
C. The cells become diploid
D. The chromosome number is halved because homologous pairs
separate
Answer: D
Rationale: After meiosis I, each cell is haploid (n), though each
chromosome still has two chromatids.
7. A human cell with 46 chromosomes undergoes meiosis. How many
chromosomes are in each cell at the end of meiosis II?
A. 46
B. 23
C. 92
D. 12
Answer: B
Rationale: The four daughter cells are haploid with 23 single-chromatid
chromosomes each.
8. Independent assortment occurs during:
A. Prophase II
B. Metaphase I, when tetrads orient randomly at the metaphase plate
C. Telophase II
D. S phase
Answer: B
Rationale: The orientation of each homologous pair is independent of the
others, so maternal and paternal chromosomes are distributed randomly.
BIO 1201 Exam 3 - Page 3
