Unit 4 AP Biology
What is expected percent change in the DNA content 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%
The cell cycle of yeast cells grown in the nutrient-poor environment is approximately what percent of the cell cycle of yeast cells grown in the nutrient-rich environment?
168
Based on figure 1, what percent of the time required to complete a full cycle do the cells typically spend in interphase?
95%
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
Which of the following describes a mutation that would lead to an increase in the frequency of nondisjunction?
A mutation affecting checkpoint 3 proteins that prevents attachment of spindle fibers
Which of the following best describes the production of DMSP by coral and coral symbionts?
A negative feedback mechanism that reverses the environmental change
The energy required to run the calvin cycle reactions of photosynthesis comes from which two substances produced during the light-dependent reactions?
ATP and NADPH
Which of the following best explains the buildup of lactic acid in individuals with the mutation?
Cells undergo fermentation because pyruvate cannot be metabolized to proceed into the krebs cycle
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.
Which of the following research questions would best guide an investigation of the link between the structure of the signaling molecules and the evolution of quorum sensing?
Did these species evolve from a common ancestor that used a similar signaling molecule?
Which of the following best describes the role of mitosis in the cell cycle?
Distributing replicated chromosomes to daughter nuclei
Which of the following best describes the role of cyclin in the regulation of the cell cycle?
During M phase, the cyclin level peaks, resulting in an increased binding frequency with CDK
Based on figure 1, which of the following best explains how exercise causes blood glucose to rise?
Epinephrine activates alpha cells, causing the release of glucagon, and inhibits beta cells, blocking the release of insulin
Which of the following research questions is best addressed by the experiment?
How to chemical messengers affect a cells transition between the phases of the cell cycle?
Which of the following best describes the most likely defect in muscle cells of patients with type 2 diabetes?
IRS-1 activation is reduced at high insulin concentrations
Which of the following patterns are shown by the data?
In mutant 3 cells, more time is spent in prophase/prometaphase than in the later stages of mitosis
Which of the following best describes the effect of insulin binding to the receptor on the osteoblast cells?
Insulin binding ultimately increases pancreatic secretion of additional insulin
Which of the following best supports the claim that drug X inhibits oxygen consumption?
Melanoma line 3 consumes statistically less oxygen per cell in the presence of drug X than it does in the presence of the solvent alone
A researcher examining a root tip observes a plant cell with condensed sister chromatids, kinetochores with attached microtubules, and individual chromosomes that are aligned at the equatorial plate of the cell. Which of the following best describes what the next process will be in the cell?
Paired chromatids will separate, and the new daughter chromosomes will move toward opposite poles of the cell.
During mitosis, which of the following normally occurs?
Replicated chromosomes line up on the equatorial plate
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
Which of the following best describes the effect on a drug that blocks the production of the mitotic cyclin?
The cell would be prevented from entering mitosis, and the cell would 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
Which of the following statements best describes how a growth factor stimulates cell division from outside a cell?
The growth factor binds to receptors on the cell surface, initiating a signal transduction pathway that activates specific target genes.
Which of the following best justifies the claim that osteocalcin is a hormone?
The osteoblasts in the bone secret osteocalcin, which causes cells in the pancreas to change their activity.
Which of the following best explains the results of the experiment?
The pH of the treatment culture was lower than the pH of the control because the chemical increased the bacterial metabolic rate
Which of the following observations provides the best evidence that acetyl-CoA negatively regulates pyruvate dehydrogenase activity?
The rate of the pyruvate dehydrogenase catalyzed reaction is slower in the presence of a higher concentration of acetyl-CoA
Which of the following best explains the most likely method by which this antitumor drug works?
Trabectedin interferes with the duplication of DNA during interphase and thus prevents cancer cells from passing the G2 checkpoint.
Which of the following best explains the effects of rotenone on cellular respiration?
Treated cells are not able to break down NADH because certain enzymes of the electron transport chain are inhibited
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.