Forms of the Ras protein found in tumors usually cause which of the
following?
A) DNA replication to stop
B) DNA replication to
be hyperactive
C) cell-to-cell adhesion to be
nonfunctional
D) cell division to cease
E) growth factor
signaling to be hyperactive
growth factor signaling to be hyperactive
A genetic test to detect predisposition to cancer would likely
examine the APC gene for
involvement in which type(s) of
cancer?
A) colorectal only
B) lung and breast
C) small
intestinal and esophageal
D) lung only
E) lung and prostate
colorectal only
In colorectal cancer, several genes must be mutated in order to
contribute to a cell
developing into a cancer cell, supporting
Knudsen's hypothesis. Which of the following kinds
of
genes would you expect to be mutated?
A) genes coding for
enzymes that act in the colon
B) genes involved in control of the
cell cycle
C) genes that are especially susceptible to
mutation
D) the same genes that Knudsen identified as associated
with retinoblastoma
E) the genes of the bacteria that are
abundant in the colon
genes involved in control of the cell cycle
Muscle cells differ from nerve cells mainly because they
A)
express different genes.
B) contain different genes.
C) use
different genetic codes.
D) have unique ribosomes.
E) have
different chromosomes.
express different genes
Cell differentiation always involves
A) the production of
tissue-specific proteins, such as muscle actin.
B) the movement
of cells.
C) the transcription of the myoD gene.
D) the
selective loss of certain genes from the genome.
E) the
cell's sensitivity to environmental cues, such as light or heat.
the production of tissue-specific proteins, such as muscle actin.
Apoptosis involves all but which of the following?
A)
fragmentation of the DNA
B) cell-signaling pathways
C)
activation of cellular enzymes
D) lysis of the cell
E)
digestion of cellular contents by scavenger cells
lysis of the cell
Absence of bicoid mRNA from a Drosophila egg leads to the absence of
anterior larval body
parts and mirror-image duplication of
posterior parts. This is evidence that the product of the
bicoid
gene
A) is transcribed in the early embryo.
B) normally
leads to formation of tail structures.
C) normally leads to
formation of head structures.
D) is a protein present in all head
structures.
E) leads to programmed cell death.
normally leads to formation of head structures.
Proto-oncogenes can change into oncogenes that cause cancer. Which of
the following best
explains the presence of these potential time
bombs in eukaryotic cells?
A) Proto-oncogenes first arose from
viral infections.
B) Proto-oncogenes normally help regulate cell
division.
C) Proto-oncogenes are genetic
"junk."
D) Proto-oncogenes are mutant versions
of normal genes.
E) Cells produce proto-oncogenes as they age.
Proto-oncogenes normally help regulate cell division.