Chapter 11
What is the role of the protein FtsZ in prokaryotes?
It forms a ring at the site of constriction.
Which of the following are true regarding CDKs?
The levels of CDKs change with the cell cycle.
T or F Nondisjunction can occur in both mitosis and meiosis.
True
a zygote is
a diplod
What type of protein is being activated by the G1 /S cyclin-CDK complex to promote the expression of histone genes?
a transcription factor
The microtubules that form the mitotic spindle extend out from the centrosome. Where would you expect to find the plus (fast-assembling) end of a spindle microtubule?
away from the centrosome and toward the kinetochore
Which of the following are part of the process of binary fission in prokaryotes?
formation of a new cell wall
A malignant cancer differs from a benign tumor in that:
malignant cancers invade surrounding tissue and benign cancers do not
In which phase of mitosis do chromosomes condense?
prophase
Crossing over occurs during which step in meiosis?
prophase I
Cell cycle checkpoints:
provide opportunities to check if the cell has carried out steps necessary for cell division, can be blocked by the protein p53, act as a brake on cell division if something is not right
Reproduction by mitotic cell division:
results in two daughter cells that are genetically identical.
A couple has a baby that only has one X chromosome and no Y chromosome. This could have occurred because:
-there was nondisjunction of the paired X and Y chromosomes in meiosis I in the father. Meiosis in the mother was normal. -there was nondisjunction of sister chromatids in meiosis II of the father. Meiosis in the mother was normal. -there was nondisjunction of homologous chromosomes in meiosis I in the mother. Meiosis in the father was normal. -there was nondisjunction of the sister chromatids in meiosis II in the mother. Meiosis in the father was normal.
Which statement regarding cancer, according to Douglas Hanahan and Robert Weinberg, are true?
Cancer cells can sometimes metastasize and travel throughout the body. Mutations in growth factor receptors are sometimes required for cancer cell division. Cancer cells can resist cell-death signals. Cancer cells typically secrete factors that promote blood vessel formation.
Which of the following is a characteristic of meiotic cell division?
Cell division results in the production of gametes.
Which are the functions of cyclins?
Cyclins activate kinases that regulate passage of cell cycle checkpoints.
Which statement regarding the cell cycle is true?
It is regulated by cyclins and CDKs., Different levels of cyclins are observed at different cell cycle stages, It can be "paused" by the action of p53, It has many major cell cycle checkpoints
Why would a compound that interferes with bacterial cell wall synthesis be useful for treating a bacterial infection?
It would limit growth of the bacterial population through cell division.
A researcher is studying phases of the cell cycle in a population of cells during which there is an increase in the DNA content. This stage is most likely:
S phase
Replication of DNA in a eukaryote occurs during which phase of the cell cycle?
S phase
Mitotic cell division is considered asexual because:
the daughter cells receive DNA from one parent cell, and the daughter cells are genetically identical.
Synapsis is best described as:
the pairing of homologous chromosomes in prophase I.
The alignment of chromosomes at metaphase of meiosis II is most similar to the alignment of chromosomes during metaphase of mitosis.
true