2026/2027
BIO 311D Final Exam 2026/2027 Advanced
Study Guide for Test Bank Preparation,
Revision Exercises, and Comprehensive
Exam Success
Question 1:
Which statement best compares mitosis and meiosis in terms of chromosome number
and genetic outcome?
A. Mitosis produces haploid cells; meiosis produces diploid cells
B. Mitosis produces genetically diverse cells; meiosis produces identical cells
C. Mitosis maintains chromosome number; meiosis reduces it by half
D. Both processes produce identical daughter cells
Correct Answer: C. Mitosis maintains chromosome number; meiosis reduces it
by half
Rationale:
Mitosis produces two genetically identical diploid (2n) daughter cells, preserving
chromosome number for growth and repair. Meiosis produces four genetically diverse
haploid (n) cells by reducing chromosome number by half, which is essential for
sexual reproduction. Options A and B are reversed, while D is incorrect because
meiosis introduces genetic variation.
Question 2:
A species has a diploid number (2n) of 50. How many homologous chromosome pairs
are present?
A. 50
B. 25
C. 100
D. 75
Correct Answer: B. 25
Rationale:
Homologous pairs represent matched chromosomes (one from each parent). Since
diploid number is 50, the number of pairs is half: 25. The other options misinterpret
chromosome structure or ploidy.
,2026/2027
Question 3:
How many chromosomes would be found in a sperm cell of the same species
described above?
A. 50
B. 25
C. 100
D. 75
Correct Answer: B. 25
Rationale:
Gametes are haploid (n), meaning they contain half the diploid number. Therefore, a
sperm cell would contain 25 chromosomes. This ensures restoration of diploidy upon
fertilization.
Question 4:
Which statement best distinguishes sexual reproduction from asexual reproduction?
A. Sexual reproduction produces identical offspring
B. Asexual reproduction requires meiosis
C. Sexual reproduction involves fusion of gametes
D. Asexual reproduction increases genetic diversity
Correct Answer: C. Sexual reproduction involves fusion of gametes
Rationale:
Sexual reproduction involves the fusion of haploid gametes (sperm and egg), leading
to genetic diversity. Asexual reproduction typically uses mitosis and produces
genetically identical offspring. Options A, B, and D are incorrect.
Question 5:
Which term refers to the genetic makeup of an organism?
A. Phenotype
B. Genotype
C. Allele
D. Trait
Correct Answer: B. Genotype
Rationale:
Genotype refers to the genetic composition (DNA) of an organism, while phenotype
, 2026/2027
refers to observable traits. Alleles are versions of genes, and traits are expressed
characteristics.
Question 6:
An organism with two identical alleles for a gene is described as:
A. Heterozygous
B. Homozygous
C. Dominant
D. Recessive
Correct Answer: B. Homozygous
Rationale:
Homozygous individuals have two identical alleles (AA or aa). Heterozygous
organisms have two different alleles. Dominant and recessive refer to expression
patterns, not allele pairing.
Question 7:
Which statement correctly describes dominant alleles?
A. Expressed only when homozygous
B. Always masked by recessive alleles
C. Expressed whenever present
D. Require environmental triggers
Correct Answer: C. Expressed whenever present
Rationale:
Dominant alleles are expressed in both homozygous dominant and heterozygous
conditions. Recessive alleles require two copies to be expressed.
Question 8:
In incomplete dominance, the heterozygous phenotype is:
A. Identical to dominant
B. Identical to recessive
C. Intermediate between both
D. Randomly expressed
Correct Answer: C. Intermediate between both
BIO 311D Final Exam 2026/2027 Advanced
Study Guide for Test Bank Preparation,
Revision Exercises, and Comprehensive
Exam Success
Question 1:
Which statement best compares mitosis and meiosis in terms of chromosome number
and genetic outcome?
A. Mitosis produces haploid cells; meiosis produces diploid cells
B. Mitosis produces genetically diverse cells; meiosis produces identical cells
C. Mitosis maintains chromosome number; meiosis reduces it by half
D. Both processes produce identical daughter cells
Correct Answer: C. Mitosis maintains chromosome number; meiosis reduces it
by half
Rationale:
Mitosis produces two genetically identical diploid (2n) daughter cells, preserving
chromosome number for growth and repair. Meiosis produces four genetically diverse
haploid (n) cells by reducing chromosome number by half, which is essential for
sexual reproduction. Options A and B are reversed, while D is incorrect because
meiosis introduces genetic variation.
Question 2:
A species has a diploid number (2n) of 50. How many homologous chromosome pairs
are present?
A. 50
B. 25
C. 100
D. 75
Correct Answer: B. 25
Rationale:
Homologous pairs represent matched chromosomes (one from each parent). Since
diploid number is 50, the number of pairs is half: 25. The other options misinterpret
chromosome structure or ploidy.
,2026/2027
Question 3:
How many chromosomes would be found in a sperm cell of the same species
described above?
A. 50
B. 25
C. 100
D. 75
Correct Answer: B. 25
Rationale:
Gametes are haploid (n), meaning they contain half the diploid number. Therefore, a
sperm cell would contain 25 chromosomes. This ensures restoration of diploidy upon
fertilization.
Question 4:
Which statement best distinguishes sexual reproduction from asexual reproduction?
A. Sexual reproduction produces identical offspring
B. Asexual reproduction requires meiosis
C. Sexual reproduction involves fusion of gametes
D. Asexual reproduction increases genetic diversity
Correct Answer: C. Sexual reproduction involves fusion of gametes
Rationale:
Sexual reproduction involves the fusion of haploid gametes (sperm and egg), leading
to genetic diversity. Asexual reproduction typically uses mitosis and produces
genetically identical offspring. Options A, B, and D are incorrect.
Question 5:
Which term refers to the genetic makeup of an organism?
A. Phenotype
B. Genotype
C. Allele
D. Trait
Correct Answer: B. Genotype
Rationale:
Genotype refers to the genetic composition (DNA) of an organism, while phenotype
, 2026/2027
refers to observable traits. Alleles are versions of genes, and traits are expressed
characteristics.
Question 6:
An organism with two identical alleles for a gene is described as:
A. Heterozygous
B. Homozygous
C. Dominant
D. Recessive
Correct Answer: B. Homozygous
Rationale:
Homozygous individuals have two identical alleles (AA or aa). Heterozygous
organisms have two different alleles. Dominant and recessive refer to expression
patterns, not allele pairing.
Question 7:
Which statement correctly describes dominant alleles?
A. Expressed only when homozygous
B. Always masked by recessive alleles
C. Expressed whenever present
D. Require environmental triggers
Correct Answer: C. Expressed whenever present
Rationale:
Dominant alleles are expressed in both homozygous dominant and heterozygous
conditions. Recessive alleles require two copies to be expressed.
Question 8:
In incomplete dominance, the heterozygous phenotype is:
A. Identical to dominant
B. Identical to recessive
C. Intermediate between both
D. Randomly expressed
Correct Answer: C. Intermediate between both
