BIO 311D Organismal Biology, Ecology, and Evolution Final Exam
Study Set, 2026/2027 – 75-Question Integrative Biology Examination
with Verified
Be able to use these terms correctly: DNA molecule, chromosome, chromatid,
homologous pair. - CORRECT ANSWERS-DNA molecule: 1 molecule of double
stranded DNA, aka chromosome
Chromosome: one molecule of DNA and associated proteins
Chromatid: condensed form of chromosomes, often found in form of sister
chromatids. These are two chromatids that are identical and attached together
at the centromere. These separate in meiosis II
Homologous pair: one chromosome from the mom and one chromosome from
the dad. These are not identical but have the same gene loci in the same order.
Write out a general life cycle with arrows linking these terms: haploid (n),
diploid (2n), meiosis, fertilization. - CORRECT ANSWERS-DIPLOID -> meiosis -
> HAPLOID -> fertilization -> DIPLOID
Are the products of meiosis haploid or diploid? - CORRECT ANSWERS-haploid
Define sexual reproduction and asexual reproduction. How do they differ in
comparison of genetic traits between parents and offspring? For each, at what
points are mitosis and meiosis involved? - CORRECT ANSWERS-Asexual: a
single individual is the sole parent and passes copies of all its genes to its
offspring without the fusion of gametes. This is done strictly through mitosis.
The daughter cells/offspring are completely identical to the parent.
Sexual: two parents combine their haploid gametes produced through meiosis
to create a diploid offspring. The offspring is not identical to either parent but
share same general traits.
,In animal life cycles, do diploid cells undergo mitosis? In life cycles of the great
majority of animals, including humans, do haploid cells undergo mitosis? Is that
the same case for plants? - CORRECT ANSWERS-Animal: diploid somatic cells
undergo mitosis, diploid germ cells undergo meiosis.
Plants: alternation of generations. 2n multicellular sporophyte undergoes
meiosis to create 1n spores. These spores divide mitotically to create a
multicellular haploid organism called gametophyte. These 1n cells create
gametes through mitosis. These gametes fuse to create a diploid zygote which
develops into the next sporophyte. IN SUMMATION: haploid cells undergo
mitosis in plants
What are homologous chromosomes? Is a homologous pair the same as a pair of
twin chromatids? - CORRECT ANSWERS-Homologous chromosomes are two
chromosomes with the same gene loci in the same order but not the same
alleles. These are not the same as twin chromatids because TC are identical
while HC are not.
How does meiosis I differ from meiosis II? Do the members of a homologous
pair separate from each other at meiosis I or meiosis II? At what point do
identical chromatids separate from each other? - CORRECT ANSWERS-
Homologous chromosomes separate from each other at meiosis I, sister
chromatids separate from each other at meiosis II.
If the diploid number for a species is 54, what is the haploid number for that
species? - CORRECT ANSWERS-27
If a cell with genome of 20 pairs of chromosomes undergoes normal meiosis,
how many cells result and how many chromosomes are in each of he resulting
cells. - CORRECT ANSWERS-4 cells result, 20 chromosomes in each
, If cell with 2n=40 chromosomes undergoes meiosis, but one nondisjunction
event occurs during meiosis II, how many chromosomes will be in each of the 4
daughter cells. - CORRECT ANSWERS-20, 20, 19, 21
If a diploid cell has n pairs of chromosomes, how many different combinations
of haploid chromosomes can be produced in meiosis of that cell? Does
independent assortment of homologous chromosomes during meiosis I produce
a large amount of genetic variation even without considering crossing over and
random fertilization? What's 2^23 - CORRECT ANSWERS-2^n different
combinations. This is because every tetrad can be assorted in two different ways
due to independent assortment. It produces a large amount of variation, more
than crossing over. 2^23 is about 8 million.
What is crossing-over (recombination)? Does it occur in meiosis I? in meiosis II?
Tell why. - CORRECT ANSWERS-DNA molecules in homologous pairs
(nonsister chromatids) are broken off and rejoined to the other homologous
chromosome. Piece of the maternal chromatid is placed on paternal chromatid
and vice versa. This occurs at chiasma. Crossing over occurs in meiosis I. Crossing
over occurs to increase genetic variation in the offspring.
What is the evolutionary advantage of diploidy? - CORRECT ANSWERS-To
versions of the same gene: if one doesn't work, the other one can produce
proteins and work in it's place.
Distinguish asexual reproduction from sexual reproduction. - CORRECT
ANSWERS-Sexual reproduction requires two parents while asexual
reproduction only requires one parent. Offspring of asexual reproduction will be
genetically identical to the parent while offspring of sexual will have genetic
variation. Asexual reproduction occurs through mitosis while sexual
reproduction occurs through meiosis.
Study Set, 2026/2027 – 75-Question Integrative Biology Examination
with Verified
Be able to use these terms correctly: DNA molecule, chromosome, chromatid,
homologous pair. - CORRECT ANSWERS-DNA molecule: 1 molecule of double
stranded DNA, aka chromosome
Chromosome: one molecule of DNA and associated proteins
Chromatid: condensed form of chromosomes, often found in form of sister
chromatids. These are two chromatids that are identical and attached together
at the centromere. These separate in meiosis II
Homologous pair: one chromosome from the mom and one chromosome from
the dad. These are not identical but have the same gene loci in the same order.
Write out a general life cycle with arrows linking these terms: haploid (n),
diploid (2n), meiosis, fertilization. - CORRECT ANSWERS-DIPLOID -> meiosis -
> HAPLOID -> fertilization -> DIPLOID
Are the products of meiosis haploid or diploid? - CORRECT ANSWERS-haploid
Define sexual reproduction and asexual reproduction. How do they differ in
comparison of genetic traits between parents and offspring? For each, at what
points are mitosis and meiosis involved? - CORRECT ANSWERS-Asexual: a
single individual is the sole parent and passes copies of all its genes to its
offspring without the fusion of gametes. This is done strictly through mitosis.
The daughter cells/offspring are completely identical to the parent.
Sexual: two parents combine their haploid gametes produced through meiosis
to create a diploid offspring. The offspring is not identical to either parent but
share same general traits.
,In animal life cycles, do diploid cells undergo mitosis? In life cycles of the great
majority of animals, including humans, do haploid cells undergo mitosis? Is that
the same case for plants? - CORRECT ANSWERS-Animal: diploid somatic cells
undergo mitosis, diploid germ cells undergo meiosis.
Plants: alternation of generations. 2n multicellular sporophyte undergoes
meiosis to create 1n spores. These spores divide mitotically to create a
multicellular haploid organism called gametophyte. These 1n cells create
gametes through mitosis. These gametes fuse to create a diploid zygote which
develops into the next sporophyte. IN SUMMATION: haploid cells undergo
mitosis in plants
What are homologous chromosomes? Is a homologous pair the same as a pair of
twin chromatids? - CORRECT ANSWERS-Homologous chromosomes are two
chromosomes with the same gene loci in the same order but not the same
alleles. These are not the same as twin chromatids because TC are identical
while HC are not.
How does meiosis I differ from meiosis II? Do the members of a homologous
pair separate from each other at meiosis I or meiosis II? At what point do
identical chromatids separate from each other? - CORRECT ANSWERS-
Homologous chromosomes separate from each other at meiosis I, sister
chromatids separate from each other at meiosis II.
If the diploid number for a species is 54, what is the haploid number for that
species? - CORRECT ANSWERS-27
If a cell with genome of 20 pairs of chromosomes undergoes normal meiosis,
how many cells result and how many chromosomes are in each of he resulting
cells. - CORRECT ANSWERS-4 cells result, 20 chromosomes in each
, If cell with 2n=40 chromosomes undergoes meiosis, but one nondisjunction
event occurs during meiosis II, how many chromosomes will be in each of the 4
daughter cells. - CORRECT ANSWERS-20, 20, 19, 21
If a diploid cell has n pairs of chromosomes, how many different combinations
of haploid chromosomes can be produced in meiosis of that cell? Does
independent assortment of homologous chromosomes during meiosis I produce
a large amount of genetic variation even without considering crossing over and
random fertilization? What's 2^23 - CORRECT ANSWERS-2^n different
combinations. This is because every tetrad can be assorted in two different ways
due to independent assortment. It produces a large amount of variation, more
than crossing over. 2^23 is about 8 million.
What is crossing-over (recombination)? Does it occur in meiosis I? in meiosis II?
Tell why. - CORRECT ANSWERS-DNA molecules in homologous pairs
(nonsister chromatids) are broken off and rejoined to the other homologous
chromosome. Piece of the maternal chromatid is placed on paternal chromatid
and vice versa. This occurs at chiasma. Crossing over occurs in meiosis I. Crossing
over occurs to increase genetic variation in the offspring.
What is the evolutionary advantage of diploidy? - CORRECT ANSWERS-To
versions of the same gene: if one doesn't work, the other one can produce
proteins and work in it's place.
Distinguish asexual reproduction from sexual reproduction. - CORRECT
ANSWERS-Sexual reproduction requires two parents while asexual
reproduction only requires one parent. Offspring of asexual reproduction will be
genetically identical to the parent while offspring of sexual will have genetic
variation. Asexual reproduction occurs through mitosis while sexual
reproduction occurs through meiosis.
