Unit 3 Questions
Meiosis I, meiosis II and mitosis have similarities and differences. A major difference between meiosis I and mitosis is that during meiosis I
- homologous non-sister chromatids exchange alleles by crossing over. - Tetrads
Snails are hermaphrodites, reproduce sexually, are diploid, and have 24 chromosomes (n=12). Where do the chromosomes in a snail zygote come from?
12 from a sperm cell, 12 from an egg
Cats reproduce sexually, are diploid and have 38 chromosomes (n=19). Where do the chromosomes in a cat zygote come from?
19 from a sperm cell, 19 from an egg
Where do the chromosomes in a human zygote come from?
23 from a sperm cell, 23 from an egg
How many double helices of DNA are in a tetrad?
4
You start with one cell where the number of types of chromosomes (n) is equal to ten, and watch it undergo meiosis. At the end of telophase II and cytokinesis II you would see
4 cells with 10 chromosomes
One duplicated chromosome has two sister chromatids. In prophase of mitosis you see 12 duplicated chromosomes in a cell. This cell type has n of
6
By definition, the number of types of chromosomes is n. For a given cell, n = 16. How many double helices of DNA are there during G2 of the mitotic cell cycle?
64
Sister chromatids are made by
DNA synthesis during S phase.
Mitosis
Diploid to Diploid; the numbers don't change
Meiosis I
Diploid to Haploid
Of the following, which would happen most immediately before the separation of the sister chromatids during the mitotic cell cycle?
G2 phase
Of the following, which would happen next after the synthesis of DNA during the mitotic cell cycle?
G2 phase
Starting at the G1 phase of the mitotic cell cycle, which of the following would come next?
G2 phase
Meiosis II
Haploid
Fertilization
Haploid to Diploid
There is one gene for protein H. It is called gene H. Gene H has alleles G and g in the population you are studying. Which of the following is always true?
If one allele for gene H is on chromosome 4, then an allele for gene H is at the same locus on the other copy of chromosome 4.
What is an advantage of sexual reproduction compared to asexual reproduction?
It generates genetic diversity.
Centromeres
Located in the center of the "X", they hold the chromatids together in a chromosome. They also help the chromosomes attach to the spindle fibers.
Which of the following happens FIRST during the mitotic cell cycle?
Microtubules emerge from the centrosomes.
Sister chromatids are made during
S phase of the mitotic and meiotic cell cycles.
Which of the following situations is most likely if a eukaryotic cell is stuck at the M checkpoint?
The cell is in mitosis with all but two of the chromosomes aligned on the metaphase plate.
Of the events below, which would happen LAST in the mitotic cell cycle after the DNA was replicated?
The plasma membrane would form a cleavage furrow and would divide the cell into two daughter cells.
Which of the following situations is most likely if a eukaryotic cell is stuck at the G2 checkpoint?
There are errors in the replication of the DNA.
Imagine you work in a lab and prepared two Petri dishes with plenty of nutrients and exactly the same density of cultured skin cells. The density starts at 1000 cells per dish. The cells are low enough density that they are not touching each other. The professor you work with asked you to test substance X to see if it is a growth factor. Which experiment and result would most strongly support the hypothesis that substance X is a growth factor?
You add X to both dishes; when you count later they each have 3000 cells.
Which of the following organisms is using asexual reproduction?
a budding hydra
During cytokinesis
actin microfilaments divide the cell into two cells.
Imagine you are working in a lab and want cells in a Petri dish to divide. What would you do?
add growth factors and nutrients
You would find sister chromatids
after DNA replication and before metaphase.
Unlike during mitosis, during meiosis homologous chromosomes
align with each other as tetrads on the metaphase plate.
Sister chromatids separate from each other during
anaphase II
If a cell is stopped at the M checkpoint, it will not enter the next phase of mitosis, which is
anaphase.
The actin microfilaments of the cytoskeleton
are small in diameter and divide the cell during cytokinesis
Sexually transmitted diseases
can be cured with antibiotics if they are bacterial and caught early.
Which of the following lists includes things that happen to the cytoskeleton during the mitotic cell cycle in the correct order?
centrosomes duplicate, mitotic spindles form, microtubules pull sister chromatids apart, cytokinesis
Which of the following is a bacterial sexually transmitted disease, and therefore treatable with antibiotics?
chlamydia
When actin microfilaments divide a cell into two cells during the mitotic cell cycle it is
cytokinesis.
Removing growth factors from the environment around dividing cells is most likely going to
decrease the rate of cell division.
During prophase I and metaphase I the cells are _________, and during prophase II and metaphase II they are ____________.
diploid, haploid
For this question, the cells divide in response to activation of the growth factor receptor, but not cell density. If a cell had a mutation that caused a growth factor receptor to be stuck in the shape it normally had when growth factors were bound, then you would expect cells with this mutation to
divide more frequently than usual.
The cytoskeleton plays a big role in the mitotic cell cycle. Actin microfilaments are used in the mitotic cell cycle for
dividing the cell in two during cytokinesis.
You would find sister chromatids
during the G2 phase of the cell cycle.
In a cell that will undergo meiosis to make sperm cells, one copy of each type of chromosome came from the mother and the other copy came from the father of the organism. During meiosis
each daughter cell usually has alleles from each parent.
In a cell that will undergo meiosis to make sperm cells, one copy of each type of chromosome came from the mother and the other copy came from the father of the organism. During meiosis
each sperm cell usually has alleles from each parent.
What are the correct names, in order for the stages of mammalian development?
egg, zygote, blastocyst, embryo, fetus, infant
Which of the following refers to a type of sexual reproduction?
fertilization of an egg
You start with one cell where the number of types of chromosomes (n) is equal to twelve, and watch it undergo meiosis. At the end of telophase II and cytokinesis II you would see
four cells, each with twelve chromosomes.
Sexual reproduction is more advantageous than asexual reproduction when
genetic diversity is important for the survival of some of the organisms.
Homologous chromosomes are two chromosomes of the same type. Homologous chromosomes
have different alleles.
Assuming there are no mutations, sister chromatids
have identical DNA sequences to each other.
Assuming no mutations or crossing over events, sister chromatids
have the same alleles as each other.
Homologous chromosomes do NOT
have the same alleles.
Sister chromatids
have the same length
Assuming no mutations or crossing over events, homologous chromosomes
have the same lengths as each other
Assuming no mutations or crossing over events, sister chromatids
have the same lengths as each other.
Plant cells and animal cells both undergo mitosis and cytokinesis. New cell wall material is deposited from vesicles
in plant cells during cytokinesis.
Which of the following would be most likely to lead to cancer?
smoking
In a human, the prostate
is a valve that lets only urine or only semen into the urethra.
You look at a cell and see 19 tetrads on the metaphase plate. From this information you would know that
it is a non-human cell in metaphase I.
Which type of contraception also gives some protection against sexually transmitted diseases?
latex condoms
Exactly one copy of each type of chromosome is in each daughter cell after
meiosis
You are studying cells where the number of types of chromosomes (n) is equal to four. You look down the microscope and see one cell with four duplicated chromosomes lined up on the metaphase plate. This cell is in
metaphase II of meiosis.
You are studying cells where the number of types of chromosomes (n) is equal to seven. You look down the microscope and see one cell with seven duplicated chromosomes lined up on the metaphase plate. This cell is in
metaphase II of meiosis.
You are studying cells where the number of types of chromosomes (n) is equal to nine. You look down the microscope and see one cell with eighteen duplicated chromosomes lined up on the metaphase plate. This cell is in
metaphase of mitosis.
You are studying cells where the number of types of chromosomes (n) is equal to seven. You look down the microscope and see one cell with fourteen duplicated chromosomes lined up individually on the metaphase plate. This cell is in
metaphase of mitosis.
Which happens next after fertilization in the human life cycle?
mitosis of diploid cells
During anaphase II of meiosis, the chromosomes
move to opposite poles of the cell.
During anaphase, the chromosomes
move to opposite poles of the cell.
During synapsis and crossing over
new combinations of alleles are created.
There is exactly one double helix of DNA in
one non-duplicated chromosome.
Where does fertilization normally take place?
oviduct
Assume no mutations for this question. You are studying a multicellular animal. All of the cells that are NOT dividing have
pairs of homologous chromosomes with one from the mom and one from the dad.
During meiosis
plasma membranes undergo cytokinesis at the end of meiosis I and meiosis II.
When does the nuclear envelope dissolve?
prophase and prometaphase
Which of the following is LEAST likely to directly involve the cytoskeleton?
repairing mutations when the DNA is replicated incorrectly.
Exposing cells to growth factors is most likely going to
send the cells through the G1 checkpoint.
Which of the following is a type of contraception that prevents fertilization by chemically preventing the sperm from fertilizing the egg?
spermicides
When there are mistakes in the replication of DNA during the mitotic cell cycle, the cell is most likely going to
stop at the G2 checkpoint.
The new nuclear envelopes are forming around the daughter chromosomes at opposite poles of a cell in mitosis. This cell is in
telophase.
In a man, the sperm are released into the seminiferous tubules of the _________ in the scrotum, before traveling through the epididymus.
testicle
Which of the following happens FIRST of the steps of meiosis listed below?
tetrads of duplicated homologous chromosomes form (during prophase) homologous chromosomes separate (during anaphase)
Which of the following happens first of the following steps of fertilization?
the acrosome reaction
During the human life cycle
the adults and zygotes are diploid.
Where does a blastocyst implant for a normal pregnancy?
the endometrium of the uterus
The purpose of _______________ is making more cells to repair wounds and replace dead cells, for asexual reproduction of single-celled eukaryotes, and for growth during development.
the mitotic cell cycle
Which of the following happens LAST during the mitotic cell cycle?
the nuclear envelopes reform around the chromosomes. The cleavage furrow forms
You are working with environmental contaminants, and have found chemical A in the water supply. You are concerned it is a growth factor, so you run experiments to test this hypothesis. You have two sets of identical flasks of cells, set 1 and set 2. You add chemical A to set 1, but do not add chemical A to set 2. You wait a three days and measure the number of cells again. The data that is most convincing that chemical A is a growth factor would be
the number of cells in set 1 is larger than the number in set 2 at the end of the experiment.
You are working with environmental contaminants, and have found chemical A in the water supply. You are concerned it is a growth factor, so you run experiments to test this hypothesis. You have two sets of identical flasks of cells, set 1 and set 2. You do not add chemical A to set 1, but you add chemical A to set 2. You wait three days and measure the number of cells again. The data that would be most convincing that chemical A is a growth factor would be
the number of cells in set 1 is smaller than the number in set 2 at the end of the experiment.
Which part of the female reproductive system is where meiosis occurs?
the ovaries
In a human, the egg travels from
the ovary through the oviduct to the uterus through the cervix and vagina.
Which of the following is LEAST likely to prevent fertilization and/or implantation?
the rhythm method
Which of the following has to happen last during mitosis?
the sister chromatids move to opposite poles of the cell
Which of the following has to occur during mitosis before anaphase?
the spindle microtubules attach to the kinetochores
Which of the following has to occur during mitosis before metaphase?
the spindle microtubules attach to the kinetochores
In a human, the sperm travel from
the testes through the epididymis and vas deferens then urethra.
Of the following choices, in humans the next location a sperm cell would be found in after being in the vas deferens would be
the urethra.
Which of the following prevents multiple sperm from fertilizing an egg?
the vitelline reaction
Which of the following prevents polyspermy?
the vitelline reaction
During the meiotic cell cycle
there are two rounds of cytokinesis.
The purpose of the mitotic cell cycle is
to generate a daughter cell that is identical to the cell that divides.
The purpose of the meiotic cell cycle is
to generate haploid gametes for sexual reproduction.
The purpose of mitosis is
to get exactly one copy of each chromosome into each daughter cell.
The purpose of mitosis is
to get exactly one copy of each chromosome to each daughter cell.
The purpose of meiosis is
to get exactly one copy of each type of chromosome into each daughter cell.
The purpose of the meiosis (not the whole meiotic cell cycle) is
to get exactly one copy of each type of chromosome into each daughter cell.
When do cells divide by going through the meiotic cell cycle?
to make sperm
The purpose of the meiotic cell cycle is for the starting cell
to produce haploid gametes.
When do cells divide by going through the mitotic cell cycle?
to replace dead cells
When in the life cycle are there meiotic cell divisions?
when gametes are made in the gonads
