AP Bio Cell Cycle
What is the expected percent change in the DNA content of a typical eukaryotic cell as it progresses through the cell cycle from the start of the G1 phase to the end of the G2 phase?
+100%
A plant cell has 12 chromosomes at the end of mitosis. How many chromosomes would it have in the G2 phase of its next cycle?
12
How many chromatids would the cell with 12 chromosomes have in the G2 phase of its cell cycle?
24
A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei containing how many chromosomes
92
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.
Centromeres uncouple, sister chromatids are separated, and the two new chromosomes move to opposite poles of the cell
Anaphase
Cells growing in cell culture that divide and pile up on top of each other are lacking
Anchorage dependence
Knowledge of the cell cycle control system will be most beneficial to the area of
Cancer prevention and treatment
Glycogen synthetase kinase 3 beta is a protein kinase that has been implicated in many types of cancer. Depending on the cell type, the gene for glycogen synthetase kinase 3 beta (GSK3β) can act either as an oncogene or as a tumor suppressor. Which of the following best predicts how GSK3β mutations can lead to the development of cancer?
Cells with inactive GSK3β fail to trigger apoptosis.
All of the following occur during prophase of mitosis in animal cells accept
Chromosomes are duplicated
Figure 1. Number of chromosomes in a human cell at different stages of cell division Which of the following presents a correct interpretation of the changes in chromosome number depicted in Figure 1 ?
Chromosomes enter metaphase containing two chromatids attached by a centromere. During anaphase, the chromatids are separated, each becoming a chromosome. Cytokinesis distributes the chromosomes into two separate cells
Which of the following would not be exhibited by cancer cells
Density- Dependent inhibition
Which of the following best describes the role of mitosis in the cell cycle?
Distributing replicated chromosomes to daughter nuclei
A cell in which of the phases would have the least amount of DNA
G0
Nerve and muscle cells are in this phase
G0
most cells that will no longer divide are in this phase
G0
The "restriction point" occurs here
G1
The "restriction point" occurs here:
G1
Figure 1. Percent of cells in phases of mitosis Which of the following patterns is shown by the data?
In mutant 3 cells, more time is spent in prophase/prometaphase than in the later stages of mitosis.
The longest part of the cell cycle is
Interphase
Which of the following is not true of a cell plate
It results from the fusion of microtubules
In a plant cell, a centrosome functions in the formation of
Microtubules in the spindle apparatus
DNA is replicated at this time of the cell cycle
S phase
chromosomes replicate
S phase of interphase
Most cells that have become transformed into cancer cells have which of the following characteristics when compared to normal, healthy cells?
Shorter cell cycle
Figure 1. Amount of DNA per cell during different stages of the cell cycle, relative to the beginning of the G1stage Which of the following best describes how the amount of DNA in the cell changes during M phase?
The amount of DNA is halved as the cell divides into two daughter cells.
Based on the model of eukaryotic cell cycle regulation shown in the figure, which of the following best describes the effect of a drug that blocks the production of the mitotic cyclin?
The cell would be prevented from entering mitosis, and the cell would stop dividing.
One of the major differences in the cell division of prokaryotic cells compare to eukaryotic cells is that
The chromosomes do not separate along a mitotic spindle in prokaryotic cells
How do the daughter cells at the end of mitosis and cytokinesis compare with their parent cell when it was in G1 of the cell cycle?
The daughter cells have the same number of chromosomes and DNA.
Cancer cells behave differently than normal body cells. For example, they ignore signals that tell them to stop dividing. Which of the following conditions will most likely cause a normal body cell to become a cancer cell?
The environment contains mutagens that induce mutations that affect cell-cycle regulator proteins.
. that number of chromosomes will be found in. That number of chromosomes will be found in
The somatic cells
What is a chromatid
a replicate chromosome
sister chromatids separate and chromosomes move apart
anaphase
dA protein maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active
cdk
The centromere is a region in which
chromatids are attached to one another
If chemical signals in the cytoplasm control the progression of a cell to the M phase of the cell cycle, then fusion of a cell in G1 with a cell in early M phase would most likely result in the
condensation of chromatin in preparation of nuclear division in both cells
A protein synthesized at a specific time during the cell cycle that associates with a kinase to form a catalytically active complex
cyclin
Cell plate forms in plant cells
cytokinesis
sister chromatids
each have their own kinetochore
Chromosomes line up in the middle of the cell
metaphase
kinetochore microtubules interactions move chromosomes to midline
pro metaphase
chromosomes become visible
prophase
mitotic spindle begins to form
prophase
A general term for enzymes that activate or inactivate other proteins by phosphorylating them
protein kinesis
nuclear membranes form around separated chromosomes
telophase
DNA replication occurs
the S phase of interphase in both somatic and reproductive cells
In animal cells, cytokinesis involves
the contraction of the contractile ring of microfilaments