The person credited with first recognizing (in the 1860s) that living cells cannot arise spontaneously, but arise only from previously existing cells, is _____.
are genetically identical to the parent cell (assuming no mutation has occurred
The function of the mitotic cell cycle is to produce daughter cells that _____.
Sister chromatids are produced during _____, which is when DNA replication occurs.
The complex of DNA and protein that makes up a eukaryotic chromosome is properly called _____.
The region of a chromosome holding the two double strands of replicated DNA together is called _____.
sister chromatids are attached to one another in prophase
The centromere is a region in which _____.
How many maternal chromosomes are present in a somatic human cell not engaged in cell division?
A cell entering the cell cycle with 32 chromosomes will produce two daughter cells, each with _____.
division of the cytoplasm
"Cytokinesis" refers to _____.
identical copies of each other if they are part of the same chromosome
Chromatids are _____.
If a cell contains 60 chromatids at the start of mitosis, how many chromosomes will be found in each daughter cell at the completion of the cell cycle?
between the G1 and G2 phases
A biochemist measured the amount of DNA in cells growing in the laboratory and found that the quantity of DNA in the cells doubled _____.
A cell biologist carefully measured the quantity of DNA in grasshopper cells growing in cell culture. Cells examined during the G2 phase of the cell cycle contained 200 units of DNA. What would be the amount of DNA at G1 of the cell cycle in one of the grasshopper daughter cells?
dispersed in the nucleus as long strands of chromatin
During interphase, the genetic material of a typical eukaryotic cell is _____.
the S phase of interphase in both somatic and reproductive cells
DNA replication occurs in _____.
If a somatic human cell is just about to divide, it has _____ chromatids.
Down syndrome is characterized by cells having three copies of chromosome 21. As a cell in an individual with Down syndrome prepares to enter mitosis, how many chromatids would be present?
replication of chromosomes
Which of the following does NOT occur during mitosis?
During what phase in the cell cycle would you find the most DNA per cell?
In telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in _____.
Which of the following phases of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope?
Assume that you are dealing with a species in which the number of chromosomes in each somatic cell is 14. How many sister chromatids are present in the early telophase of mitosis?
In a human skin cell that is going through the cell cycle, when do the centrosomes separate?
Following cytokinesis in an animal cell, how many centrioles does each new daughter cell possess?
The phase of mitosis during which the chromosomes move toward separate poles of the cell is _____.
the beginning of the formation of a spindle apparatus
One event occurring during prophase is _____.
metaphase: the nuclear envelope disappears
Which of the following represents a mismatch or incorrect description?
During which stage of the cell cycle do sister chromatids separate?
In animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle?
At which stage of mitosis are chromosomes lined up in one plane in preparation for their separation to opposite poles of the cell?
it had formed a cell plate
You would know a dividing cell was a plant cell rather than an animal cell if you saw that _____.
binary fission replication of DNA separation of the origins of replication inward growth of the plasma membrane
Which of the following processes occur in dividing bacteria?
the origins of replication move apart
During binary fission in a bacterium _____.
distribution of a copy of the single parental chromosome to each daughter cell
Which of the following is involved in the binary fission of bacteria?
DNA synthesis begins immediately in the original G1 nucleus
When a cell in S phase is fused with a cell in G1, _____.
fibroblasts fail to divide
fibroblasts fail to divide
Tissue culture experiments with PDGF demonstrate that without this substance _____.
You would be unlikely to see which of the following human cells dividing?
do not exhibit density-dependent inhibition
Observations of cancer cells in culture support the hypothesis that cancer cells _____.
Cells of benign tumors do not metastasize; those of malignant tumors do
What is the difference between a benign tumor and a malignant tumor?
a plant cell in the process of cytokinesis.
Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely
disruption of mitotic spindle formation.
Vinblastine is a standard chemotherapeutic drug used to treat cancer. Because it interferes with the assembly of micro-tubules, its effectiveness must be related to
continue to divide even when they are tightly packed together.
One difference between cancer cells and normal cells is that cancer cells
the degradation of cyclin.
The decline of MPF activity at the end of mitosis is due to
cells with more than one nucleus
In the cells of some organisms, mitosis occurs without cytoki-nesis. This will result in
replication of the DNA
Which of the following does not occur during mitosis? spindle formation replication of the DNA separation of sister chromatids condensation of the chromosomes separation of the spindle poles
A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in
cleavage furrow formation and cytokinesis
The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?
chromosomes, or genetic material, must be copied, which occurs during interphase
What must happen before a cell can begin mitosis?
The centrosomes move away from each other and the nuclear envelope breaks up during which phase of mitosis?
The chromosomes line up in the center of the cell during which phase of mitosis?
The sister chromatids separate and begin moving toward opposite poles of the cell during which phase of mitosis?
The chromosomes arrive at the poles and nuclear envelopes form during which phase of mitosis?
At the end of the mitotic (M) phase, the cytoplasm divides in a process called _________________.
growth and development tissue repair/replacement of damaged cells
In sexually reproducing multicellular organisms, the main functions of mitosis are
The nuclear envelope breaks down. Chromosomes condense and are attached to spindle fibers.
Which events occur during prophase? Chromosomes are replicated. The nuclear envelope breaks down. Chromosomes condense and are attached to spindle fibers. The sister chromatids break apart and begin to separate. b and c only
finishes mitosis by dividing the cytoplasm and organelles of the original parent cell into two separate daughter cells
During _____, the cell carries out its normal functions and the chromosomes are thinly spread out throughout the nucleus.
Looking through a light microscope at a dividing cell, you see two separate groups of chromosomes on opposite ends of the cell. New nuclear envelopes are taking shape around each group. The chromosomes then begin to disappear as they unwind. You are witnessing _____.