Biology chapter 11 test
What structure is found in prokaryotic cells but not eukaryotic cells?
A single, circular DNA chromosome found in the cytoplasm.
The p53 protein is involved in DNA repair and in triggering cell death when repair is not possible. Why are some cancers associated with defective p53 genes?
Because cells with damaged DNA are not triggered to die. Because cell growth and division is no longer regulated by p53 proteins. Because cells with damaged DNA growth and divided uncontrollably.
The two cells are provided with nutrients for growth. After 35 hours, which is the most likely observation of the cells?
Cell 2 has divided twice, while cell 1 has divided once.
diagram?
Differentiation is the process by which cells become specialized. The inner mass of cells of the blastocyst will form the specialized cells in the body.
Chromatids are distributed to the two daughter nuclei.
G1
At the end of this phase, each chromosome is made up of two chromatids.
G2
Chose two correct answers.
In both C. elegans and Drosophila, a cell's final specialization can be mapped early in the animal's development. In both C. elegans and Drosophila, cells differentiate into a number of distinct cell types.
Organelles and materials needed for DNA synthesis are made.
M
Proteins and other materials needed for cell division are sythesized.
S
Wich saftey assessments should be confirmed?
Stem cells should not have harmful mutations. Stem cells should not spread beyond the site of the transplant. Stem cells treatment should not cause tumors.
Wich of the following events is best represented by the diagram?
The binding of DNA by histones.
Wich additional observation would provides the strongest evidence that Paramecium reproduces asexually?
The cells in the colony are genetically identical.
Which of the following happends when cancer occurs?
The control of the cell cycle is impaired.
If a cubical cell with 2-cm sides doubles the dimensions of its sides, what changes occurs to the ratio of its surface area to volume?
The ratio is halved.
Which of the following statements are typical for cancer cells?
They tend to hbe unspecialized. They may form tumors that metasize. They have defective genes.
Why do cells divide?
To ensure that a cell does not become too large. To produce new cells during an organism's growth. To replace damaged cells and tissues.
If the side of a cubical cell doubled, what would the cell then require?
To excrete eight times more waste.
What useful purpose is served by cell division in a multicellular organism?
To replace damadged cells and tissues.
This process causes death of normal cells
apoptosis
This process regulates the cell cycle.
apoptosis
Bacteria reproduce _________ through cell fission. A tube of cytoplasm can temporarily connect two bacterial cells to transfer genetic information, Some DNA passes through this tube. Like ______ reproduction it causes genetic variation. However, it does not produce offspring.
asexually, sexual
They are non-differentiated cells.
cancer cell
The cells have an abnormal nucleus.
cancer cells
The cells undergo metastasis.
cancer cells
Look at this picture, what does it represent?
cell division
This process increased number of body cells.
cell division
This process produces specialized cells.
cell division
This process repairs injuries.
cell division
The __________ is the point of attachment for sister chromatids.
centromere
The __________ is an area from which the spindle fibers extend.
centrosome
Cells with DNA damadge undergo apoptosis.
normal cells
The cells are differentiated and specialized.
normal cells
The cells have a normal nucleus.
normal cells