Final Exam Flashcards
Which of the following is released by platelets in the vicinity of an injury? A. Cdk B. cyclin C. PDGF D. MPF
C. PDGF
A research team began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away?
A. The cells are unable to form spindle microtubules.
B. The cells show characteristics of tumors.
C. They have altered the series of cell cycle phases.
D. They were originally derived from an elderly organism.
B. The cells show characteristics of tumors
If there are 20 centromeres in a cell at anaphase, how many chromosomes are there in each daughter cell following cytokinesis? A. 80 B. 10 C. 40 D. 20
B. 10
Movement of the chromosomes during anaphase would be most affected by a drug that prevents \_\_\_\_\_. A. elongation of microtubules B. formation of a cleavage furrow C. nuclear envelope breakdown D. shortening of microtubules
D. shortening of microtubules
The drug cytochalasin B blocks the function of actin. Which of the following aspects of the cell cycle would be most disrupted by cytochalasin B?
A. cleavage furrow formation and cytokinesis
B. spindle attachment to kinetochores
C. cell elongation during anaphase
D. spindle formation
A. cleavage furrow formation and cytokinesis
In a plant’s sexual life cycle _____.
A. gametophytes produce gametes by meiosis
B. gametophytes produce gametes by mitosis
C. sporophytes produce gametes by mitosis
D. sporophytes produce gametes by meiosis
B. gametophytes produce gametes by mitosis
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, II, and IV
B. II, IV, and V
C. I, II, III, IV, and V
D. II, III, and IV
D. II, III, and IV
Starting with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells? A. 16 B. 8 C. 32 D. 64
C. 32
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 half of their nuclear genes to each of their offspring.
C. Asexual reproduction produces only haploid offspring.
D. In asexual reproduction, offspring are produced by fertilization without meiosis.
B. In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
Imagine that there are twenty-five different species of protists living in a tide pool. Some of these species reproduce both sexually and asexually, and some of them can reproduce only asexually. The pool gradually becomes infested with disease-causing viruses and bacteria. Which species are more likely to thrive in the changing environment?
A. the asexually reproducing species
B. Sexually and asexually reproducing species are equally likely to thrive.
C. the sexually reproducing species
D. protists cannot survive in a tide pool
C. the sexually reproducing species
How do cells at the completion of meiosis compare with cells that are in prophase of meiosis I? They have _____.
A. half the number of chromosomes and one-fourth the amount of DNA.
B. half the number of chromosomes and half the amount of DNA.
C. the same number of chromosomes and half the amount of DNA.
D. half the amount of cytoplasm and twice the amount of DNA.
A. half the number of chromosomes and one-fourth the amount of DNA.
Which of the following happens at the conclusion of meiosis I?
A. The chromosome number per cell remains the same.
B. Homologous chromosomes of a pair are separated from each other.
C. Sister chromatids are separated.
D. Sister chromatids are separated.
B. Homologous chromosomes of a pair are separated from each other.
When we first see chiasmata under a microscope, we know that \_\_\_\_\_. A. anaphase II has occurred B. meiosis II has occurred C. prophase I is occurring D. separation of homologs has occurred
C. prophase I is occurring
Homologous pairs of chromosomes align opposite of each other at the equator of a cell during \_\_\_\_\_. A. mitosis metaphase B. meiosis metaphase I C. meiosis telophase II D. meiosis metaphase II
B. meiosis metaphase I
Which of the following occurs in meiosis but not in mitosis?
A. alignment of chromosomes at the equator
B. synapsis of chromosomes
C. condensation of chromosomes
D. chromosome replication
B. synapsis of chromosomes
The bulldog ant has a diploid number of two chromosomes. Therefore, following meiosis, each daughter cell will have a single chromosome. Diversity in this species may be generated by mutations and _____.
A. nothing else
B. independent assortment
C. crossing over
D. crossing over and independent assortment
D. crossing over and independent assortment
A triploid cell contains sets of three homologous 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 21 sets of 3
B. 63 chromosomes in 31 half pairs
C. 21 chromosome pairs and 21 unique chromosomes
D. 63 chromosomes, each with three chromatids
A. 63 chromosomes in 21 sets of 3
The somatic cells of a privet shrub each contain 46 chromosomes. How do privet chromosomes differ from the chromosomes of humans, who also have 46?
A. Genes of privet chromosomes are significantly different than those in humans.
B. Privet sex cells have chromosomes that can synapse with human chromosomes in the laboratory.
C. Privet cells cannot reproduce sexually.
D. Privet shrubs must be metabolically more like animals than like other shrubs.
A. 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, centromere position, and staining pattern only
B. length, centromere position, staining pattern, and traits coded for by their genes
C. They have nothing in common except that they are X-shaped.
D. length and position of the centromere only
B. length, centromere position, staining pattern, and traits coded for by their genes
For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes? A. about 1000 B. 23 C. 46 D. about 8 million
D. about 8 million
Mendel continued some of his experiments into the F2 or F3 generation to _____.
A. distinguish which alleles were segregating
B. observe whether or not a recessive trait would reappear
C. obtain a larger number of offspring on which to base statistics
D. observe whether or not the dominant trait would reappear
B. observe whether or not a recessive trait would reappear
The individual with genotype AaBbCCDdEE can make many kinds of gametes. Which of the following is the major reason?
A. different possible assortment of chromosomes into gametes
B. the tendency for dominant alleles to segregate together
C. crossing over during prophase I
D. recurrent mutations forming new alleles
A. different possible assortment of chromosomes into gametes
Why did the F1 offspring of Mendel’s classic pea cross always look like one of the two parental varieties?
A. No genes interacted to produce the parental phenotype.
B. Each allele affected phenotypic expression.
C. One allele was dominant.
D. The traits blended together during fertilization.
C. One allele was dominant.
Mendel's observation of the segregation of alleles in gamete formation has its basis in which of the following phases of cell division? A. anaphase I of meiosis B. anaphase II of meiosis C. metaphase II of meiosis D. prophase I of meiosis
A. anaphase I of meiosis