Cell Division I
TRUE OR FALSE.
Homologous chromosomes contain the same genes but are inherited from different parents.
TRUE
Which of the following is not a way bacterial cells can achieve genetic diversity?
a. conjugation
b. binary fission
c. transduction
d. transformation
b. binary fission
Which comes immediately after S phase in the cell cycle?
a) G1
b) G2
c) mitosis
d) cytokinesis
b) G2
Which gives the most complete and correct description of a signal transduction pathway?
a) binding of a signal molecule to a cell protein
b) catalysis mediated by an enzyme
c) sequence of changes in a series of molecules resulting in a response
d) binding of a ligand on one side of a membrane that results in a change on the other side
e) the cell’s detection of a chemical or mechanical stimulus
c) sequence of changes in a series of molecules resulting in a response
Which of the following types of signaling requires direct contact between cells?
a. synaptic signaling
b. endocrine signaling
c. paracrine signaling
d. signaling between gap junctions
e. signaling between ion channel receptors
d. signaling between gap junctions
Which phase of MITOSIS do sister chromatids become chromosomes?
a. prophase
b. prometaphase
c. metaphase
d. anaphase
e. telophase
d. anaphase
Crossing over occurs during:
a. prophase I
b. prophase II
c. metaphase I
d. metaphase II
a. prophase I
Which best describes the kinetochore?
a) a structure composed of several proteins that associate with the centromere region of a chromosome and that can bind to spindle microtubules
b) the centromere region of a metaphase chromosome where the DNA can bind with spindle proteins
c) the array of vesicles that will form between two dividing nuclei and give rise to the metaphase plate
d) the ring of actin microfilaments that will cause the appearance of the cleavage furrow
e) the core of proteins that forms the cell plate in a dividing plant cell
a) a structure composed of several proteins that associate with the centromere region of a chromosome and that can bind to spindle microtubules
Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) are secreted by the pituitary gland in the brain, and they cause ovulation to occur. Which type of communication is this an example of?
a) Autocrine signaling
b) Paracrine signaling
c) Endocrine signaling
d) Synaptic signaling
c) Endocrine signaling
This step of signal transduction involves a protein phosphorylation cascade.
a. Quorom sensing
b. Reception
c. Transduction
d. Response
c. Transduction
Which of the following stages of mitosis is incorrectly paired?
a. PROPHASE - DNA is replicated
b. METAPHASE - chromosomes line up along the imaginary equatorial plane
c. ANAPHASE - sister chromatids separate and become chromosomes
d. TELOPHASE - the nuclear envelope forms around each set of chromosomes
a. PROPHASE - DNA is replicated
Occurs when chromosomes are improperly separated during Meiosis I or Meiosis II.
a. crossing over
b. independent assortment
c. nondisjunction
d. fertilization
c. nondisjunction
If you were given a slide and told that the cells on it were performing cytokinesis, how would you tell if you had plant cells or animal cells?
a) Look for a cell plate or a cleavage furrow.
b) Look for condensed or decondensed chromosomes.
c) Look for an intact or a dispersed nuclear membrane.
d) Look for more or less layers in the cell wall.
a) Look for a cell plate or a cleavage furrow.
What happens when a signal binds to its receptor?
a) It changes form.
b) The cell switches the message.
c) The nucleus tells calcium ions to alter gene expression.
d) cAMP amplifies the signal.
e) Cells die on purpose.
a) It changes form.
Which is the best example of amplification of signal?
a) production of many molecules by many signal molecules
b) activation of 100 molecules by a single signal binding event
c) activation of a specific gene by a transcription factor
d) conversion of the signal into many other types of molecules
e) activation of a receptor by a hormone
b) activation of 100 molecules by a single signal binding event
A cell with 10 chromosomes undergoes mitosis. ____ daughter cells are produced, each with ___ chromosomes.
2; 10
How and at what stage is independent assortment accomplished?
a) pairing of homologs during meiosis I
b) separation of homologs during anaphase II
c) separation of homologs during meiosis II
d) metaphase alignment during meiosis I
e) telophase separation during meiosis I
d) metaphase alignment during meiosis I
Mitosis:
From the pole to the chromosome, what is the correct order?
a) centrosome, microtubule, kinetochore, chromosome
b) microtubule, kinetochore, chromosome, centrosome
c) centrosome, kinetochore, microtubule, chromosome
d) centrosome, kinetochore, chromosome, microtubule
a) centrosome, microtubule, kinetochore, chromosome
Which correctly describes the use of ligand-gated ion channel receptors?
a) Ligand binding is irreversible, resulting in a permanent change in this ion channel’s activity.
b) The binding site of this type of receptor is most often in the middle of the membrane.
c) Once activated, this receptor will cause G proteins to bind with GTP.
d) Once the ligand is bound, the ion channel activity can alter the local membrane potential and cytosolic concentration of the ion.
e) The ligand involved is often a phosphate group that is covalently added to the cytosolic side of this ion channel.
d) Once the ligand is bound, the ion channel activity can alter the local membrane potential and cytosolic concentration of the ion.
Phosphorylation of proteins in a kinase cascade during signal transduction does what?
a) makes functional ATP
b) distorts a protein from one functional state to another
c) alters the permeability of the cell’s membranes
d) produces an increase in the cell’s store of inorganic
phosphates
b) distorts a protein from one functional state to another
You are observing a line of rat cells and see that they repeatedly make mistakes in the cell cycle by going through the G2 checkpoint too early. This could be due to a. . .
a) problem with expression of a cyclin.
b) misplaced MPF.
c) defective chromosome.
d) misfolded centromere protein.
a) problem with expression of a cyclin.
Why does sexual reproduction (via meiosis) have an advantage over asexual reproduction (via mitosis)?
a) Meiosis is more efficient at producing offspring.
b) Meiosis allows two parents to invest resources in offspring.
c) Meiosis allows for more competition.
d) Meiosis increases genetic variation among offspring.
d) Meiosis increases genetic variation among offspring.
From prophase through metaphase of mitosis, each chromosome has _____ DNA molecules, while from anaphase through telophase of mitosis, each chromosome has _____ DNA molecule(s).
a) two; one
b) 2n; 1n
c) homologous; nonhomologous
d) condensed; decondensed
e) non-sister chromatid; sister chromatid
a) two; one
If you wanted to block signaling involving a steroid molecule, which should you destroy?
a) plasma membrane
b) endoplasmic reticulum
c) ribosomes
d) nuclear pores
d) nuclear pores
A steroid hormone is bound by an intracellular receptor. The resulting complex is most likely to do what?
a) open channels in the membrane for other substances to enter
b) open channels in the nuclear envelope for cytoplasmic molecules to enter
c) mediate the transfer of phosphate groups to/from ATP
d) act as a transcription factor in the nucleus
e) enable water-soluble molecules to diffuse across membranes
d) act as a transcription factor in the nucleus