Mastering Biology Chapter 8
In a cell containing 10 chromosomes, meiosis results in the formation of daughter cells containing _____ chromosomes.
5
Imagine that a human skin cell went through mitosis but did not undergo cytokinesis. How many chromosomes would be in the cell?
92
A pair of sex chromosomes found in a human male is most like
A bride and groom
Which of the following checkpoints does not occur late in G1?
A check that chromosome replication has been successfully completed
Which of the following statements regarding the differences between mitosis and meiosis is false?
Crossing over is a phenomenon that creates genetic diversity during mitosis.
The process by which the cytoplasm of a eukaryotic cell divides to produce two cells is called
Cytokinesis
A benign tumor differs from a malignant tumor in that a benign tumor
Does not metastasize
Nucleoli are present during _____.
Interphase
The genetic material is duplicated during
The S phase
Which of the following statements regarding the cell cycle control system is false?
The cell-cycle control system operates independently of the growth factors
During _____ chromosomes align single file along the equator of a haploid cell.
metaphase II
How many pairs of autosomes do humans have?
22
A certain species of animal has six pairs of chromosomes. How many DNA molecules are present in the nuclei of these animals during G2 phase?
24
When observing a chicken skin cell in G2 under a microscope, you count 156 total chromatids. How many chromosomes does a male chicken have in its sperm cells?
39
During anaphase II, _____.
sister chromatids separate and migrate toward opposite poles
The kinetochores are __________.
sites at which microtubules attach to chromosomes
An example of a cell that is 2n is a __________.
somatic cell
Cytokinesis often, but not always, accompanies _____
telophase
At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids.
telophase I
During mitosis, the chromosomes move because _____.
they attach to a dynamic, precisely regulated mitotic spindle
Looking into your microscope, you spot an unusual cell. Instead of the typical rounded cell shape, the cell has a very narrow middle separating two bulging ends. It sort of looks like the number 8! You realize that this cell is
undergoing cytokinesis
During what phase of Meiosis does synapsis occur
Prophase I
During binary fission, each copy of the duplicating chromosome moves to opposite ends of the cell. What does this achieve?
It ensures that each daughter cell receives one copy of the chromosome.
In the telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in _____.
Prophase
Which of the following statements correctly describes the behavior of a tetrad during anaphase I of meiosis?
it splits into two pairs of sister chromatids and one pair goes to each pole of the dividing cell
When we say that an organism is haploid, we mean that __________.
its cells each have one set of chromosomes
Spindle fibers attach to kinetochores during _____.
prometaphase
Synapsis occurs during _____.
prophase I
Which of the following shows mitosis in the correct chronological order?
prophase, prometaphase, metaphase, anaphase, telophase
Both mitosis and meiosis are preceded by
Interphase
Which of the following statements regarding the function of mitosis is false?
Mitosis allows organisms to generate genetic diversity
Which of the following statements regarding mitosis and meiosis is false?
Mitosis produces daughter cells with half the number of chromosomes as the parent cell.
Chromosomes become visible during ___ .
Prophase
Crossing over is important because it _____.
allows the exchange of genes between homologous chromosomes
Centromeres divide and sister chromatids become full-fledged chromosomes during _____.
anaphase
During _____ sister chromatids separate.
anaphase II
Mature human nerve cells and muscle cells
are permanently in a state of nondivision.
A cleavage furrow forms in an animal cell during _____.
cytokinesis
Meiosis II typically produces _____ cells, each of which is _____.
four ... haploid
The function of meiosis is to make __________.
four cells with a haploid number of chromosomes
True or false. Mitosis takes place during M phase of the cell cycle, which is longer than interphase.
False
You are observing a single cell under a microscope. You go home for the night, and the next day you see four cells. The four cells look similar, and when you stain them with a dye that binds to DNA they all appear to contain the same amount of DNA. What likely happened overnight?
The single cell divided to form two new cells, and the two new cells each divided to form four total cells, all by asexual reproduction.
Meiosis I produces _____ cells, each of which is _____.
two ... haploid
During prophase a homologous pair of chromosomes consists of _____.
two chromosomes and four chromatids.
Mitosis and cytokinesis result in the formation of __________; meiosis and cytokinesis result in the formation of __________.
two diploid cells : four haploid cells
The creation of genetically identical offspring by a single parent, without the participation of sperm and egg, is called
Asexual Reproduction
During which phase of mitosis does the nuclear envelope re-form?
Telophase
During cell division, what role do centrosomes play?
They organize the microtubules.
