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Review Questions
Review Questions
1.
A diploid cell has how many times the number of chromosomes as a haploid cell?
- four times
- half
- one-fourth
- twice
2.
The first level of DNA organization in a eukaryotic cell is maintained by which molecule?
- cohesion
- condensin
- chromatin
- histone
3.
What inherited feature, in specific combinations, determines an organism’s traits?
- cell membranes
- genes
- proteins
- RNA
4.
What are identical copies of chromatin held together by cohesin at the centromere called?
- histones
- nucleosomes
- chromatin
- sister chromatids
5.
Chromosomes are duplicated during what stage of the cell cycle?
- G1 phase
- prophase
- prometaphase
- S phase
6.
Which of the following events does not occur during some stages of interphase?
- DNA duplication
- increase in cell size
- organelle duplication
- separation of sister chromatids
7.
Attachment of the mitotic spindle fibers to the kinetochores is a characteristic of which stage of mitosis?
- anaphase
- prophase
- prometaphase
- metaphase
8.
The fusing of Golgi vesicles at the metaphase plate of dividing plant cells forms what structure?
- actin ring
- cell plate
- cleavage furrow
- mitotic spindle
9.
What would be the outcome of blocking S phase of interphase?
- The cell would enter karyokinesis.
- DNA replication would not occur.
- Centrosomes would be duplicated.
- The cytoskeleton would be dismantled.
10.
At which of the cell cycle checkpoints do external forces have the greatest influence?
- G1 checkpoint
- G2 checkpoint
- M checkpoint
- G0 checkpoint
11.
If the M checkpoint is not cleared, what stage of mitosis will be blocked?
- prophase
- prometaphase
- metaphase
- anaphase
12.
Which protein is a positive regulator that phosphorylates other proteins when activated?
- p53
- retinoblastoma protein (Rb)
- cyclin
- cyclin-dependent kinase (Cdk)
13.
Which negative regulatory molecule can trigger apoptosis if vital cell cycle events do not occur?
- p53
- p21
- retinoblastoma protein (Rb)
- cyclin-dependent kinase (Cdk)
14.
What is the main prerequisite for clearance at the checkpoint?
- The cell has a reached a sufficient size.
- The cell has an adequate stockpile of nucleotides.
- An accurate and complete DNA replication has occurred.
- Proper attachment of mitotic spindle fibers to kinetochores has occurred.
15.
What do you call changes to the order of nucleotides in a segment of DNA that codes for a protein?
- proto-oncogenes
- tumor suppressor genes
- gene mutations
- negative regulators
16.
Human papillomavirus can cause cervical cancer. The virus encodes E6, a protein that binds p53. Based on this fact and what you know about p53, what effect do you think E6 binding has on p53 activity?
- E6 activates p53.
- E6 protects p53 from degradation.
- E6 mutates p53.
- E6 binding marks p53 for degradation.
17.
What is a gene that codes for a positive cell cycle regulator called?
- kinase inhibitor
- oncogenes
- proto-oncogenes
- tumor suppressor genes
18.
Which molecule is a Cdk inhibitor or is controlled by p53?
- anti-kinase
- cyclin
- p21
- Rb
19.
Which eukaryotic cell cycle events are missing in binary fission?
- cell growth
- DNA duplication
- karyokinesis
- cytokinesis
20.
Which of the following statements about binary fission is false?
- In both prokaryotic and eukaryotic cells, the outcome of cell reproduction is a pair of daughter cells, which are genetically identical to the parent cell.
- Karyokinesis is unnecessary in prokaryotes because there is no nucleus.
- Replication of the prokaryotic chromosome begins at the origin of replication and continues in both directions at once.
- The mitotic spindle draws the duplicated chromosomes to the opposite ends of the cell followed by formation of a septum and two daughter cells.
21.
The formation of what structure, that will eventually form the new cell walls of the daughter cells, is directed by FtsZ?
- contractile ring
- cell plate
- cytoskeleton
- septum