If a horticulturist breeding gardenias succeeds in having a single
plant with a particularly
desirable set of traits, which of the
following would be her most probable and efficient route
to
establishing a line of such plants?
A) Backtrack through
her previous experiments to obtain another plant with the same
traits.
B) Breed this plant with another plant with much weaker
traits.
C) Clone the plant asexually to produce an identical
one.
D) Force the plant to self-pollinate to obtain an identical
one.
E) Add nitrogen to the soil of the offspring of this plant
so the desired traits continue.
Clone the plant asexually to produce an identical one.
Which of the following defines a genome?
A) representation of a
complete set of a cell's polypeptides
B) the complete set
of an organism's polypeptides
C) the complete set of a
species' polypeptides
D) a karyotype
E) the complete
set of an organism's genes
Answer: E
the complete set of an organism's genes
Which is the smallest unit containing the entire human
genome?
A) one human somatic cell
B) one human
chromosome
C) all of the DNA of one human
D) the entire
human population
E) one human gene
one human somatic cell
If an organism is diploid and a certain gene found in the organism
has 18 known alleles
(variants), then any given organism of that
species can/must have which of the following?
A) at most, 2
alleles for that gene
B) up to 18 chromosomes with that
gene
C) up to 18 genes for that trait
D) a haploid number of
9 chromosomes
E) up to, but not more than, 18 different traits
at most, 2 alleles for that gene
Which of the following is a true statement about sexual vs. asexual
reproduction?
A) Asexual reproduction, but not sexual
reproduction, is characteristic of plants and fungi.
B) In sexual
reproduction, individuals transmit 50% of their genes to each of their
offspring.
C) In asexual reproduction, offspring are produced by
fertilization without meiosis.
D) Sexual reproduction requires
that parents be diploid.
E) Asexual reproduction produces only
haploid offspring.
In sexual reproduction, individuals transmit 50% of their genes to each of their offspring.
At which stage of mitosis are chromosomes usually photographed in the
preparation of a
karyotype?
A) prophase
B)
metaphase
C) anaphase
D) telophase
E) interphase
metaphase
Which of the following is true of a species that has a chromosome
number of 2n = 16?
A) The species is diploid with 32 chromosomes
per cell.
B) The species has 16 sets of chromosomes per
cell.
C) Each cell has eight homologous pairs.
D) During the
S phase of the cell cycle there will be 32 separate
chromosomes.
E) A gamete from this species has four chromosomes.
Each cell has eight homologous pairs.
Eukaryotic sexual life cycles show tremendous variation. Of the
following elements, which do
all sexual life cycles have in
common?
I. Alternation of generations
II. Meiosis
III.
Fertilization
IV. Gametes
V. Spores
A) I, IV, and
V
B) I, II, and IV
C) II, III, and IV
D) II, IV, and
V
E) I, II, III, IV, and V
II, III, and IV
Which of these statements is false?
A) In humans, each of the 22
maternal autosomes has a homologous paternal chromosome.
B) In
humans, the 23rd pair, the sex chromosomes, determines whether the
person is female
(XX) or male (XY).
C) Single, haploid (n)
sets of chromosomes in ovum and sperm unite during
fertilization,
forming a diploid (2n), single-celled
zygote.
D) At sexual maturity, ovaries and testes produce diploid
gametes by meiosis.
E) Sexual life cycles differ with respect to
the relative timing of meiosis and fertilization.
At sexual maturity, ovaries and testes produce diploid gametes by meiosis.
Referring to a plant's sexual life cycle, which of the
following terms describes the process
that leads directly to the
formation of gametes?
A) sporophyte meiosis
B) gametophyte
mitosis
C) gametophyte meiosis
D) sporophyte mitosis
E)
alternation of generations
gametophyte mitosis
Which of the following is an example of alternation of
generations?
A) A grandparent and grandchild each have dark hair,
but the parent has blond hair.
B) A diploid plant (sporophyte)
produces, by meiosis, a spore that gives rise to a
multicellular,
haploid pollen grain (gametophyte).
C) A
diploid animal produces gametes by meiosis, and the gametes undergo
fertilization to
produce a diploid zygote.
D) A haploid
mushroom produces gametes by mitosis, and the gametes undergo
fertilization,
which is immediately followed by meiosis.
E)
A diploid cell divides by mitosis to produce two diploid daughter
cells, which then fuse to
produce a tetraploid cell.
A diploid plant (sporophyte) produces, by meiosis, a spore that gives
rise to a multicellular,
haploid pollen grain (gametophyte).
The human X and Y chromosomes
A) are both present in every
somatic cell of males and females alike.
B) are about the same
size and have approximately the same number of genes.
C) are
almost entirely homologous, despite their different names.
D)
include genes that determine an individual's sex.
E) are
called autosomes.
D) include genes that determine an individual's sex.
Which of these is a karyotype?
A) a natural cellular arrangement
of chromosomes in the nucleus
B) a display of all the cell types
in an organism
C) organized images of a cell’s
chromosomes
D) the appearance of an organism
E) a display of
a cell’s mitotic stages
organized images of a cell’s chromosomes
Mitosis is commonly found in all of the following except
A) a
haploid animal cell.
B) a diploid animal cell.
C) a haploid
plant cell.
D) a diploid plant cell.
a haploid animal cell.
Which of these is a way that the sexual life cycle increases genetic
variation in a species?
A) by allowing crossing over
B) by
allowing an increase in cell number
C) by increasing gene
stability
D) by conserving chromosomal gene order
E) by
decreasing mutation frequency
by allowing crossing over
A given organism has 46 chromosomes in its karyotype. We can
therefore conclude which of
the following?
A) It must be
human.
B) It must be a primate.
C) It must be an
animal.
D) It must be sexually reproducing.
E) Its gametes
must have 23 chromosomes.
Its gametes must have 23 chromosomes.
A triploid cell contains three sets of chromosomes. If a cell of a
usually diploid species with
42 chromosomes per cell is triploid,
this cell would be expected to have which of the following?
A) 63
chromosomes in 31 1/2 pairs
B) 63 chromosomes in 21 sets of
3
C) 63 chromosomes, each with three chromatids
D) 21
chromosome pairs and 21 unique chromosomes
63 chromosomes in 21 sets of 3
Which of the following best describes a karyotype?
A) a
pictorial representation of all the genes for a species
B) a
display of each of the chromosomes of a single cell
C) the
combination of all the maternal and paternal chromosomes of a
species
D) the collection of all the chromosomes in an individual
organism
E) a photograph of all the cells with missing or extra chromosomes
a display of each of the chromosomes of a single cell
Which of the following can utilize both mitosis and meiosis in the
correct circumstances?
A) a haploid animal cell
B) a diploid
cell from a plant stem
C) any diploid animal cell
D) a
plantlike protist
E) an archaebacterium
a plantlike protist
The somatic cells of a privet shrub each contain 46 chromosomes. To
be as different as they
are from human cells, which have the same
number of chromosomes, which of the following
must be
true?
A) Privet cells cannot reproduce sexually.
B) Privet
sex cells have chromosomes that can synapse with human chromosomes in
the
laboratory.
C) Genes of privet chromosomes are
significantly different than those in humans.
D) Privet shrubs
must be metabolically more like animals than like other
shrubs.
E) Genes on a particular privet chromosome, such as the
X, must be on a different human
chromosome, such as number 18.
Genes of privet chromosomes are significantly different than those in humans.
In a human karyotype, chromosomes are arranged in 23 pairs. If we
choose one of these
pairs, such as pair 14, which of the
following do the two chromosomes of the pair have
in
common?
A) length and position of the centromere
only
B) length, centromere position, and staining pattern
only
C) length, centromere position, staining pattern, and traits
coded for by their genes
D) length, centromere position, staining
pattern, and DNA sequences
E) They have nothing in common except
they are X-shaped.
length, centromere position, staining pattern, and traits coded for by their genes
To view and analyze human chromosomes in a dividing cell, which of
the following is (are)
required?
A) a scanning electron
microscope
B) radioactive staining
C) fluorescent staining
and a transmission electron microscope
D) DNA staining and a
light microscope
E) a stain particular to human cells
DNA staining and a light microscope
The karyotype of one species of primate has 48 chromosomes. In a
particular female, cell
division goes awry and she produces one
of her eggs with an extra chromosome (25). The most
probable
source of this error would be a mistake in which of the
following?
A) mitosis in her ovary
B) metaphase I of one
meiotic event
C) telophase II of one meiotic event
D)
telophase I of one meiotic event
E) either anaphase I or II
either anaphase I or II
If a cell has completed the first meiotic division and is just
beginning meiosis II, which of the
following is an appropriate
description of its contents?
A) It has half the amount of DNA as
the cell that began meiosis.
B) It has the same number of
chromosomes but each of them has different alleles than
another
cell from the same meiosis.
C) It has half the
chromosomes but twice the DNA of the originating cell.
D) It has
one-fourth the DNA and one-half the chromosomes as the originating
cell.
E) It is identical in content to another cell from the same meiosis.
It has half the amount of DNA as the cell that began meiosis.
Which of the following might result in a human zygote with 45
chromosomes?
A) an error in either egg or sperm meiotic
anaphase
B) failure of the egg nucleus to be fertilized by the
sperm
C) fertilization of a 23 chromosome human egg by a 22
chromosome sperm of a closely related
species
D) an error in
the alignment of chromosomes on the metaphase plate
E) lack of
chiasmata in prophase I
an error in either egg or sperm meiotic anaphase
After telophase I of meiosis, the chromosomal makeup of each daughter
cell is
A) diploid, and the chromosomes are each composed of a
single chromatid.
B) diploid, and the chromosomes are each
composed of two chromatids.
C) haploid, and the chromosomes are
each composed of a single chromatid.
D) haploid, and the
chromosomes are each composed of two chromatids.
E) tetraploid,
and the chromosomes are each composed of two chromatids.
haploid, and the chromosomes are each composed of two chromatids.
How do cells at the completion of meiosis compare with cells that
have replicated their DNA
and are just about to begin
meiosis?
A) They have twice the amount of cytoplasm and half the
amount of DNA.
B) They have half the number of chromosomes and
half the amount of DNA.
C) They have the same number of
chromosomes and half the amount of DNA.
D) They have half the
number of chromosomes and one-fourth the amount of DNA.
E) They
have half the amount of cytoplasm and twice the amount of DNA.
They have half the number of chromosomes and one-fourth the amount of DNA.
When does the synaptonemal complex disappear?
A) late prophase
of meiosis I
B) during fertilization or fusion of gametes
C)
early anaphase of meiosis I
D) mid-prophase of meiosis II
E)
late metaphase of meiosis II
late prophase of meiosis I
Which of the following happens at the conclusion of meiosis
I?
A) Homologous chromosomes of a pair are separated from each
other.
B) The chromosome number per cell is conserved.
C)
Sister chromatids are separated.
D) Four daughter cells are
formed.
E) Cohesins are cleaved at the centromeres.
Homologous chromosomes of a pair are separated from each other.
Chromatids are separated from each other.
A) The statement is
true for mitosis only.
B) The statement is true for meiosis I
only.
C) The statement is true for meiosis II only.
D) The
statement is true for mitosis and meiosis I.
E) The statement is
true for mitosis and meiosis II.
The statement is true for mitosis and meiosis II.