Ap Bio Chapter 9-10
If a sperm cell contains 8 chromosomes, it comes from an animal that has ______ chromosomes.
16
Cancer can result from a variety of different mutational events. Which of the following is LEAST likely to result in the initiation of a cancerous tumor?
A defect in a cell-cycle checkpoint prevents a cell from entering the S phase.
Genetic diversity is achieved with
All of the above
Eukaryotic chromosomes
All of the choices are correct
Although the sperm and egg are both produced by the process of meiosis, they differ in which of the following ways?
All of the choices are correct.
Apoptosis
All of the choices are correct.
Homologous chromosomes
All of the choices are correct.
Sources of genetic variation in a sexually reproducing population include(s) which of the following?
All of the choices are sources of genetic variation.
What is an allele?
An allele is an alternative form of a gene.
Which of the following is NOT a difference between anaphase I and anaphase II?
Anaphase I occurs in a haploid cell while anaphase II occurs in a diploid cell
Which of the following is an incorrect statement about Meiosis I?
At the end of Meiosis I, the daughter cells have a haploid amount of DNA
Which statement is true of animal cells but not plant cells?
During cytokinesis, a cleavage furrow forms between the two forming cells.
Which is NOT true about the chromosomes of a multicellular organism?
Each chromosome separates into two daughter chromosomes by binary fission.
The p53 gene is important in cell division because it binds with Cdk to activate it
False
At which cell cycle checkpoint is the cell cycle halted if the cell's DNA is damaged?
G1 - S
Passage through which checkpoint is the step which commits the cell to proceed through to mitosis and cell division?
G1 - S
The critical G checkpoints that control the cell cycle are at the
G1 to S stage and G2 to M stage.
Which is NOT true about daughter cells of mitosis and meiosis?
In meiosis, the daughter cells are genetically identical.
Which of the following statements explains the law of independent assortment?
Inheritances of two different traits in an organism are not related to each other
What is the importance of crossing-over?
It increases the likelihood that daughter cells contain different genetic material.
Which of the following is a characteristic of the second division of meiosis (Meiosis II) in human males
It results in the separation of 23 chromosomes into daughter chromatids
A male dog has a chestnut colored coat and amber eyes. A female dog has a mahogany colored coat and blue eyes. They mate to give birth to a puppy with a mahogany colored coat and amber eyes. Which of the following laws is described here?
Law of independent assortment
In which phase of the cell cycle are the chromosomes inactive, condensed, and not transcribed to messenger RNA?
M phase
It could be said that males are able to provide gametes with more genetic diversity than females for reproduction. One main reason would be:
Males provide four functional sperm
Which is not a source of genetic variation
Mitosis
Which of the following occurs in meiosis but not in mitosis?
Pairing of homologous chromosomes at the metaphase plate
Which phrase best describes the process of crossing over
Pairs of homologous chromosomes exchange segments.
Inhibitors of DNA synthesis will act at which stage of the cell cycle
S
In which phase of the cell cycle is DNA replicated?
S phase
Which of the following correctly explains how traits are inherited independently of each other?
Separations of the alleles during gamete formation are independent of each other.
Which of the following statements is correct about the DNA content of a particular diploid cell just prior to mitosis if the DNA content of the same diploid cell in G1 is X?
The DNA content of the cell in metaphase is 2X.
Which is NOT correctly associated with cancer?
The disorganized mass of cells is encapsulated and does not invade adjacent tissue.
Which is TRUE of the cell cycle?
The timing of cell division is controlled by cyclins and CDKs.
There is a species of desert lizard in which only females are known to exist-there are no males known. It is nevertheless necessary for two females to court and for one to assume the posture of a male to stimulate the female to produce eggs. No fertilization can occur, and the eggs develop into female lizards. Which of these statements is most likely true of this lizard population?
There is little advantage to maintaining variation, but the animal has not been able to completely evolve away from its heritage of sexual reproduction.
Which of the following is NOT true about cancer cells?
They exhibit contact inhibition.
What is a tetrad?
Two homologous chromosomes in close association during meiosis I.
The polar body is
a nonfunctional cell made during oogenesis.
A cell with a defective p53 gene is likely to
accumulate chromosomal damage.
Cancer cells require lots of nutrients, which are supplied by blood vessels. The growth of new blood vessels to cancerous tissue is called:
angiogenesis
The passage of a cell through the stages of the cell cycle is controlled by protein kinases that phosphorylate many different proteins at appropriate times. What are these protein kinases called?
binding to cyclin, plus phosphorylation by a Cdk activating protein kinase
The balance between stimulatory signals and inhibitory signals determines whether
both proto-oncogenes and tumor-suppressor genes are active.
The p53 protein prevents a cell from completing the cell cycle
by acting as a tumor suppressor gene product
The nucleosome
contains histone proteins and DNA
Which of the following steps would NOT lead to variation of genetic material?
crossing over of sister chromatids
A cell that passes the restriction point will most likely
divide
DNA replication occurs
during the S phase of the cell cycle
The overall function of meiosis includes all of the following EXCEPT
growth of the overall individual.
Segregation occurs because _____________ chromosomes separate during meiosis
homologous
The two chromosomes that are members of the same pair are referred to as
homologous.
What process sets the length of time for the cell cycle to occur in eukaryotic cells?
interphase
Which genetic law describes the random distribution of the pairs of genes on different chromosomes to the gametes?
law of independent assortment.
Although cancer may originate in many regions of the body, many patients die from cancerous growth in the lungs, lymph glands, or liver. This is most readily explained as
metastasis occurring more commonly in organs that have a filter effect.
If a proto-oncogene mutated into an oncogene in an otherwise normal cell, the immediate result would most likely be
not much; perhaps a slight quickening of the cell cycle
Before the time of Gregor Mendel and genetics, sexual reproduction was thought to produce a blending or equal mixing of the parents' traits. Today we know that
offspring inherit essentially 50% of their genes from each parent, but two sibling offspring may share with each other from zero to 23 chromosomes in common from each parent, and further variation may occur due to crossing-over.
According to lecture, the cell is not allowed to pass the cell cycle restriction point if DNA damage is detected. Specifically, which is responsible for inhibiting the Cyclin and CDK Complex?
p53
During what stage of meiosis does crossing over occur?
prophase I of meiosis I
The idea that for any particular trait, genes occur in pairs and during the process of sex cell production, the members of each pair separate so that each sperm and ovum cell receives one member of each pair is Mendel's principle of:
segregation
Species X reproduces asexually by fission and species Y reproduces sexually. Consider that all other relevant characteristics are similar between these species. When the environment gradually changes, then
species Y should have a better chance of surviving than species X.
At the center of the cell cycle control system is Cdk, a protein that
that binds to the protein cyclin
The cell formed through fertilization is called a/an
zygote