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?
63 chromosomes in 21 sets of 3
Which of the life cycles is typical for plants and some algae?
III only
Which of the following is true of a species that has a chromosome number of 2n = 16?
Each cell has eight homologous pairs
Tetrads of chromosomes are aligned at the equator of the spindle; alignment determines independent assortment.
II
The human genome is minimally contained in which of the following?
Every human cell
Which of these statements is false?
At sexual maturity, ovaries and testes produce diploid gametes by meiosis.
Which diagram represents anaphase I of meiosis?
I
A karyotype results from which of the following?
the ordering of human chromosome images
Synaptonemal complexes form or are still present.
I only
Which sample of DNA might be from a nerve cell arrested in G0 of the cell cycle?
I
When we see chiasmata under a microscope, that lets us know which of the following has occurred?
prophase I
When homologous chromosomes crossover, what occurs?
Specific proteins break the two strands and re-join them with their homologs.
After telophase I of meiosis, the chromosomal makeup of each daughter cell is
haploid, and the chromosomes are each composed of two chromatids.
Which of the following is a true statement about sexual vs. asexual reproduction?
in sexual reproduction, individuals transmit 50% of their genes to each of their offspring.
Homologous chromosomes move toward opposite poles of a dividing cell during
meiosis I.
A human cell containing 22 autosomes and a Y chromosome is
a sperm
Which sample might represent an animal cell in the G2 phase of the cell cycle?
II
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?
Clone the plant asexually to produce an identical one.
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?
It has half the amount of DNA as the cell that began meiosis.
A sexually reproducing animal has two unlinked genes, one for head shape (H) and one for tail length (T). Its genotype is Hh
HT
Chromatids are separated from each other.
The statement is true for mitosis and meiosis II.
A tetrad includes which of the following sets of DNA strands?
two sets of sister chromatids that have synapsed
Which of the following occurs in meiosis but not in mitosis?
synapsis of chromosomes
Which of the following is an example of alternation of generations?
A diploid plant (sporophyte) produces, by meiosis, a spore that gives rise to a multicellular, haploid pollen grain (gametophyte).
In part III of Figure 13.1, the progression of events corresponds to which of the following series?
sporophyte, meiosis, spore, mitosis, gametophyte, mitosis, gametes, fertilization
Which of the following best describes the frequency of crossing over in mammals?
at least 1-2 per chromosome pair
Which of the steps takes place in both mitosis and meiosis?
3
Which of the following is a true statement about sexual vs. asexual reproduction?
In sexual reproduction, individuals transmit 50% of their genes to each of their offspring
If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA content of a single cell at metaphase of meiosis II would be
x
Which sample might represent a zygote?
I
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?
Length, centromere position, staining pattern, and traits coded for by their genes.
In a life cycle such as that shown in part III of Figure 13.1, if the zygote's chromosome number is 10, which of the following will be true?
The sporophyte's chromosome number per cell is 10 and the gametophyte's is 5.
If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA content of the same cell at metaphase of meiosis I would be
2x