1. In a plant's sexual life cycle _____.

gametophytes produce gametes by meiosis

1. gametophytes produce gametes by mitosis
2. sporophytes produce gametes by mitosis
3. sporophytes produce gametes by meiosis

b

Which of the following is a true statement about sexual vs. asexual reproduction?

1. In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
2. Asexual reproduction produces only haploid offspring.
3. In asexual reproduction, offspring are produced by fertilization without meiosis.
4. Asexual reproduction, but not sexual reproduction, is characteristic of plants and fungi.

a

For the duration of meiosis I, each chromosome _____.

1. consists of a single strand of DNA
2. consists of two sister chromatids joined by a centromere
3. is joined with its homologous pair to form a synaptonemal complex
4. is paired with a homologous chromosome

b

You have isolated DNA from three different cell types of the same organism, determined the relative DNA content for each type, and plotted the results on the graph shown in the figure below. Refer to the graph to answer the following question(s). Which sample might represent an animal cell in the G2 phase of the cell cycle?

1. I
2. II
3. III
4. both I and II

b

Which of the following occurs in meiosis but not in mitosis?

1. condensation of chromosomes
2. chromosome replication
3. alignment of chromosomes at the equator
4. synapsis of chromosomes

d

For the following questions, match the key event of meiosis with the stages listed below.

1. Prophase I V. Prophase II
2. Metaphase I VI. Metaphase II

III. Anaphase I VII. Anaphase II

IV. Telophase I VIII. Telophase II

Homologous chromosomes are aligned at the equator of the spindle.

1. IV
2. I
3. II
4. VI

c

1. Centromeres split and sister chromatids migrate to opposite poles in meiosis _____.
1. telophase II
2. telophase I
3. anaphase II
4. anaphase I

c

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?

1. Privet shrubs must be metabolically more like animals than like other shrubs.
2. Privet cells cannot reproduce sexually.
3. Genes of privet chromosomes are significantly different than those in humans.
4. Privet sex cells have chromosomes that can synapse with human chromosomes in the laboratory.

c

How is natural selection related to sexual reproduction as opposed to asexual reproduction?

1. Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction.
2. Sexual reproduction allows the greatest number of offspring to be produced.
3. Sexual reproduction results in the greatest number of new mutations.
4. Sexual reproduction utilizes far less energy than asexual reproduction.

a

Refer to the life cycles illustrated in the figure below to answer the following question(s). Which of the life cycles is typical for plants and some algae?

1. I only
2. II only
3. III only
4. I and III

c

The diploid number of a roundworm species is 4. Assuming there is no crossover, and random segregation of homologues during meiosis, how many different possible combinations of chromosomes might there be in the offspring (not including variety generated by crossing over)?

1. 16
2. 8
3. 4
4. 64

a

Homologous pairs of chromosomes align opposite of each other at the equator of a cell during _____.

1. mitosis metaphase
2. meiosis metaphase I
3. meiosis metaphase II
4. meiosis telophase II

b

When we first see chiasmata under a microscope, we know that _____.

1. separation of homologs has occurred
2. prophase I is occurring
3. anaphase II has occurred
4. meiosis II has occurred

b

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?

1. length, centromere position, and staining pattern only
2. length, centromere position, staining pattern, and traits coded for by their genes
3. length and position of the centromere only
4. They have nothing in common except that they are X-shaped.

b

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?

1. Breed this plant with another plant with much weaker traits.
2. Backtrack through her previous experiments to obtain another plant with the same traits.
3. Clone the plant.
4. Force the plant to self-pollinate to obtain an identical one.

c

You have isolated DNA from three different cell types of the same organism, determined the relative DNA content for each type, and plotted the results on the graph Which sample of DNA might be from a nerve cell arrested in G0 of the cell cycle?I

1. I
2. II
3. III
4. either I or II

a

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?

1. 63 chromosomes in 21 sets of 3
2. 63 chromosomes, each with three chromatids
3. 63 chromosomes in pairs
4. 21 chromosome pairs and 21 unique chromosomes

a

Which of the following can occur by the process of meiosis but not mitosis?

1. Haploid cells multiply into more haploid cells.
2. Diploid cells form haploid cells.
3. A diploid cell combines with a haploid cell.
4. Haploid cells fuse to form diploid cells.

b

What is a major difference between meiosis II and mitosis in a diploid animal?

1. Meiosis II occurs in a haploid cell, while mitosis occurs in diploid cells.
2. Crossover takes place in meiosis II.
3. Sister chromatids separate in mitosis, and homologues separate in meiosis II.
4. Homologues align on the metaphase plate in meiosis II.

a

Refer to the drawings in the figure below of a single pair of homologous chromosomes as they might appear during various stages of either mitosis or meiosis, and answer the following questions. Which diagram represents anaphase I of meiosis?

1. I
2. II
3. IV
4. V

a

Quaking aspen can send out tunderground stems for asexual reproduction. Sexual reproduction is not as common, but when it does happen, the haploid gametes have 19 chromosomes. How many chromosomes are in the cells of the underground stems?

1. 10
2. 38
3. 19
4. 9

b

After telophase I of meiosis, the chromosomal makeup of each daughter cell is _____.

1. haploid, and the chromosomes are each composed of two chromatids
2. haploid, and the chromosomes are each composed of a single chromatid
3. diploid, and the chromosomes are each composed of a single chromatid
4. diploid, and the chromosomes are each composed of two chromatids

a

Which of these is a karyotype?

1. a display of all of the cell types in an organism
2. a display of a cell’s mitotic stages
3. organized images of a cell’s chromosomes
4. the appearance of an organism

c

How do cells at the completion of meiosis compare with cells that are in prophase of meiosis I? They have _____.

1. half the amount of cytoplasm and twice the amount of DNA.
2. half the number of chromosomes and half the amount of DNA.
3. half the number of chromosomes and one-fourth the amount of DNA.
4. the same number of chromosomes and half the amount of DNA.

c

When we first see chiasmata under a microscope, we know that _____.

1. separation of homologs has occurred
2. prophase I is occurring
3. anaphase II has occurred
4. meiosis II has occurred

b

Which of the following is true of a species that has a chromosome number of 2n = 16?

1. A gamete from this species has four chromosomes.
2. The species is diploid with 32 chromosomes per cell.
3. Each diploid cell has eight homologous pairs.
4. The species has 16 sets of chromosomes per cell.

c

When homologous chromosomes cross over, what occurs?

1. Two chromatids get tangled, resulting in one re-sequencing its DNA.
2. Maternal alleles are "corrected" to be like paternal alleles and vice versa.
3. Two sister chromatids exchange identical pieces of DNA.
4. Corresponding segments of non-sister chromatids are exchanged.

d

If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in the diploid state?

1. reverse transcription
2. synapsis
3. fertilization
4. DNA replication

c

Which of the following is a true statement about sexual vs. asexual reproduction?

1. In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
2. Asexual reproduction produces only haploid offspring.
3. In asexual reproduction, offspring are produced by fertilization without meiosis.
4. Asexual reproduction, but not sexual reproduction, is characteristic of plants and fungi.

a

Asexual reproduction occurs during _____.

1. meiosis
2. fertilization
3. mitosis
4. chromosome exchange between organisms of different species

c

In meiosis, homologous chromosomes are separated during _____.

1. anaphase II
2. prophase I
3. anaphase I
4. mitosis

c

Refer to the information and figure below to answer the following question(s). A certain (hypothetical) organism is diploid, has either blue or orange wings as the consequence of one of its genes on chromosome 12, and has either long or short antennae as the result of a second gene on chromosome 19, as shown in the figure. If a female of this species has one chromosome 12 with a blue gene and another chromosome 12 with an orange gene, and has both number 19 chromosomes with short genes, she will produce which of the following egg types?

1. one-half blue short and one-half orange short gene eggs
2. three-fourths blue short and one-fourth orange short gene eggs
3. only blue short gene eggs
4. only orange short gene eggs

a

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 _____.

1. nothing else
2. independent assortment
3. crossing over
4. crossing over and independent assortment

d

Which statement best represents the connection between reproduction and evolution?

1. Since prokaryotic organisms reproduce asexually, there is no mechanism for them to add genetic diversity for evolution.
2. Sexual reproduction increases genetic variation because random mutations can be shuffled between organisms.
3. In order to increase genetic diversity for evolution in sexually reproducing organisms, mutations must occur in the zygote after fertilization.
4. Plants that use sexual reproduction are rare since this type of reproduction in plants does not contribute to genetic diversity.

b

The human X and Y chromosomes _____.

1. are the same size and have the same number of genes
2. include genes that determine an individual's sex
3. are both present in every somatic cell of males and females
4. are called autosomes

b

Independent assortment of chromosomes is a result of _____.

1. the random way each pair of homologous chromosomes lines up at the metaphase plate during meiosis I
2. the random distribution of the sister chromatids to the two daughter cells during anaphase II
3. the random combinations of eggs and sperm during fertilization
4. the diverse combination of alleles that may be found within any given chromosome

a

1. Which sample of DNA might be from a nerve cell arrested in G0 of the cell cycle?

1. I
2. II
3. III
4. either I or II

a

Eukaryotic sexual life cycles show tremendous variation. Of the following elements, which do all sexual life cycles have in common?

1. Alternation of generations
2. Meiosis
3. Fertilization
4. Gametes
5. Spores

1. I, II, and IV
2. I, II, III, IV, and V
3. II, IV, and V
4. II, III, and IV

d

A female with a paternal set of one orange and one long gene chromosome and a maternal set comprised of one blue and one short gene chromosome is expected to produce which of the following types of eggs after meiosis?

1. All eggs will have paternal types of gene combinations.
2. Half the eggs will have maternal and half will have paternal combinations.
3. Each egg has a one-fourth chance of having either blue long, blue short, orange long, or orange short combinations.
4. All eggs will have maternal types of gene combinations.

c

What is a major difference between mitosis and meiosis I in a diploid organism?

1. DNA replication takes place prior to mitosis, but not before meiosis I.
2. Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis I.
3. Only meiosis I results in daughter cells that contain identical genetic information.
4. Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis II.

b

In a life cycle such as that shown in part III of the figure above, if the zygote's chromosome number is 10, which of the following will be true?

1. The sporophyte's chromosome number per cell is 10 and the gametophyte's is 5.
2. The sporophyte's chromosome number per cell is 5 and the gametophyte's is 10.
3. The sporophyte and gametophyte each have 5 chromosomes per cell.
4. The sporophyte and gametophyte each have 10 chromosomes per cell.

a

1. Prophase I V. Prophase II
2. Metaphase I VI. Metaphase II
3. Anaphase I VII. Anaphase II
4. Telophase I VIII. Telophase II

Centromeres of sister chromatids disjoin and chromatids separate.

1. III
2. IV
3. V
4. VII

d

A certain female's number 12 chromosomes both have the blue gene and number 19 chromosomes both have the long gene. As cells in her ovaries undergo meiosis, her resulting eggs (ova) may have which of the following?

1. one chromosome 12 with one blue gene and one chromosome 19 with one long gene
2. either one blue or one orange gene in addition to either one long or one short gene
3. either two number 12 chromosomes with blue genes or two with orange genes
4. either two number 19 chromosomes with long genes or two with short genes

a

Which of the life cycles is typical for animals?

1. I and III
2. II only
3. I only
4. III only

c

Which of the following is an example of alternation of generations?

1. A diploid animal produces gametes by meiosis, and the gametes undergo fertilization to produce a diploid zygote.
2. A haploid mushroom produces gametes by mitosis, and the gametes undergo fertilization, which is immediately followed by meiosis.
3. A grandparent and grandchild each have dark hair, but the parent has blond hair.
4. A diploid plant (sporophyte) produces, by meiosis, a spore that gives rise to a multicellular, haploid pollen grain (gametophyte).

d

Which of the following happens at the conclusion of meiosis I?

1. Homologous chromosomes of a pair are separated from each other.
2. Sister chromatids are separated.
3. The chromosome number per cell remains the same.
4. Four daughter cells are formed.

a

The fastest way for organisms to adapt to a changing environment involves _____.

1. mutation
2. sexual reproduction
3. asexual reproduction

b

Which of the life cycles is typical for plants and some algae?

1. I only
2. II only
3. III only
4. I and III

c

Which of the life cycles is typical for most fungi and some protists?

1. I only
2. II only
3. III only

b

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?

1. Sexually and asexually reproducing species are equally likely to thrive.
2. the asexually reproducing species
3. the sexually reproducing species

c