cell division
Both asexual and sexual reproduction rely on _____.
nucleosomes
The “beads on a string” level of DNA packing refers to _____
92
A human bone marrow cell, in prophase of mitosis, contains 46 chromosomes. How many chromatids does it contain altogether?
they have uncoiled to form long, thin strands
It is difficult to observe individual chromosomes with a light microscope during interphase because __________.
32 chromosomes
A cell entering the cell cycle with 32 chromosomes will produce two daughter cells, each with __________.
identical copies of each other if they are part of the same chromosome
Chromatids are __________.
the S phase of interphase
DNA replication occurs during which phase of the cell cycle?
S phase
Chromatids form during which phase of the cell cycle?
large cells containing many nuclei
In some organisms, such as certain fungi and algae, cells undergo mitosis repeatedly without subsequently undergoing cytokinesis. What would be the result of this?
are genetically identical to the parent cell (assuming no mutation has occurred)
The function of the cell cycle is to produce daughter cells that __________.
division of the cell other than the nuclear material
Cytokinesis refers to __________.
prophase
In the telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in _____.
prophase
At which point in the cell cycle do centrosomes begin to separate and move to the two poles of the cell?
anaphase
The phase of mitosis during which the chromosomes move toward separate poles of the cell is _____.
the beginning of the formation of the mitotic spindle
One event occurring during prophase is __________.
Chromatids separate.
Which one of the following occurs during mitosis?
metaphase
At which stage of mitosis are chromosomes prepared for separation to opposite poles of the cell?
form a cell plate
You would recognize a dividing cell as a plant cell and not an animal cell if you saw that it had __________.
cleavage
Cytochalasin B is a chemical that disrupts microfilament formation. This chemical would interfere with __________.
cytokinesis
In animal cell mitosis, the cleavage furrow forms during _____.
Benign tumors do not metastasize; malignant tumors do.
What is the difference between a benign tumor and a malignant tumor?
autosome
iploid organisms have a pair of sex chromosomes. All of the other chromosomes are called _____.
a photograph of a person’s chromosomes
A karyotype is __________.
homologous chromosomes
Two chromosomes in a nucleus that carry genes for the same traits, but specify different versions of the same traits, are called _____.
22
How many pairs of autosomes do humans have?
its cells each have one set of chromosomes
When we say that an organism is haploid, we mean that __________.
fertilization
The diploid phase of the human life cycle begins with __________.
4 haploid cells
What is the normal result of a diploid cell undergoing meiosis?
5
In a cell containing 10 chromosomes, meiosis results in the formation of daughter cells containing _____ chromosomes.
2 haploid cells
At the end of telophase I of meiosis and cytokinesis, there are __________.
prophase 1
During meiosis, homologous chromosomes pair during _____.
sister chromatids separate and migrate toward opposite poles
During anaphase II __________.
homologues separate and migrate toward opposite poles
During anaphase I __________.
prophase 1
Crossing over occurs during _____.
4
An organism has a haploid chromosome number n = 4. How many tetrads will form during meiosis?
Pairing of homologous chromosomes occurs.
Which event occurs only during prophase I of the first meiotic division?
multiplication of body cells
Which one of the following is a function of mitosis in humans?
to make cells with a haploid (half that of the parents) number of chromosomes
What is the function of meiosis?
two diploid cells … four haploid cells
Mitosis and cytokinesis result in the formation of __________; meiosis and cytokinesis result in the formation of __________.
results in two genetically identical daughter cells
Mitosis and meiosis differ in several ways. Mitosis, but not meiosis, __________.
undergo a single round of cytokinesis
Mitosis is less complicated than meiosis because it carries out less complicated functions. Mitosis must __________.
pairing of homologous chromosomes
Which one of the following occurs in meiosis, but not in mitosis?
meiosis
Variation between mitosis and meiosis occurs when chromosomes are shuffled in _____.
They align and assort independently to form any of eight different combinations.
If the diploid number of chromosomes in a certain animal is 6 (2n = 6), there are three sets of two homologous chromosomes each, or three pairs. How do these three pairs align and separate in meiosis?
chiasmata
Sites where crossing over has occurred are called _____.
dead ends
Prior to some recent studies, such as with bdelloid rotifers, scientists thought that organisms that reproduced solely by asexual reproduction were __________.
nondisjunction
During meiosis, homologous chromosomes sometimes “stick together” and do not separate properly. This phenomenon is known as _____.
47
Each cell in an individual with Down syndrome contains _____ chromosomes.
to provide a method that creates greater genetic variation
The major contribution of sex to evolution has been __________.
