Bio 103 Chapter 10 Quiz

If a cell contains 12 chromosomes at the end of meiosis I, how many chromosomes will the daughter cells contain at the end of meiosis II?

12

If a sperm cell contains 8 chromosomes, it comes from an animal whose regular body cells have ________ chromosomes.

16

if the diploid number of chromosomes for an organism is 52, what will the haploid number of chromosomes be?

26

Which of the following is NOT true about daughter cells of mitosis or meiosis? A) In meiosis, daughter cells are haploid. B) In meiosis, there are four daughter cells. C) In mitosis, there are two daughter cells. D) In mitosis, the daughter cells are genetically identical. E) In meiosis, the daughter cells are genetically identical.

E) In meiosis, the daughter cells are genetically identical.

A change in the chromosome number resulting from nondisjunction is called euploidy. (True or False)

False

A lattice holds the members of a bivalent together in such a way that the RNA of the non-sister chromatids is aligned. (True or False)

False

A primary spermatocyte has 64 chromosomes. After meiosis I, each secondary spermatocyte would have 32 chromosomes. After meiosis II, each spermatid would have 16 chromosomes. (True or False)

False

In meiosis, the reduction from 2n to n is accomplished by sister chromatids splitting apart and migrating to opposite daughter cells.

False

Only one of the four daughter cells becomes a functional gamete in spermatogenesis. (True or False)

False

Oogenesis always involves an equal division of cell contents in the formation of an egg and polar bodies. (True or False)

False

Primary nondisjunction occurs during meiosis II when the sister chromatids fail to separate and both daughter chromosomes go in the same gamete. (True or False)

False

Spindle formation, centrosome migration, the fragmentation of the nuclear envelope, and the disappearance of the nucleolus are characteristic of prophase I of meiosis but not prophase ofmitosis. (True or False)

False

The correct number of chromosomes in a species is known as aneuploidy (True or False)

False

In human females, when is meiosis II completed?

Immediately after the sperm penetration of the secondary oocyte

During _____, the homologous chromosome pairs independently align themselves at the equator of the cell.

Independent assortment

Interkinesis is different from interphase in which way?

Interphase involves DNA replication and interkinesis does not.

Why is crossing-over important?

It increases the likelihood that daughter cells contain different genetic material.

During which stage of meiosis are the bivalents arranged along the equator of the spindle?

Metaphase I

In a particular eukaryotic organism, in which phases of meiosis and mitosis is the number of chromatids in a cell the same?

Metaphase I and Metaphase

During which stage of meiosis does crossing-over occur?

Prophase I of Meiosis I

Species X reproduces asexually by fission and species Y reproduces sexually. Consider that all other relevant characteristics are similar between these species. When the environment changes, then...

Species Y should have a better chance of surviving than species X.

Where in the human male does spermatogenesis occur?

Testes

There is a species of desert lizard in which only females are known to exist - there are no males known. It is nevertheless necessary for two females to court and for one to assume the posture of a male to stimulate the females to produce eggs. No fertilization can occur, and the eggs develop into female lizards. Which of these statements is most likely true of the lizard population?

The desert is relatively uniform and there is little advantage to maintaining variation, but the animal has not been able to completely evolve away from its heritage of sexual reproduction.

What is the function of polar bodies?

They allow a reduction in chromosomes while preserving most of the cytoplasm for one egg.

The following picture depicts which of the following changes in chromosome structure? (Different image, same concept)

Translocation

Aneuploidy is a change in the number of chromosomes resulting from nondisjunction during meiosis. (True or False)

True

It is estimated that an average of two or three cross-overs occur per human chromosome. (True or False)

True

Jacobs Syndrome, XYY, results from nondisjunction during spermatogenesis. (True or False)

True

Monosomy occurs when an individual has only one of a particular type of chromosome. (True or False)

True

Sex chromosome aneuploids are better tolerated and have a better chance of producing survivors. (True or False)

True

During which stage of meiosis do the homologous chromosomes separate?

Anaphase I

At which stage of meiosis is each chromosome composed of a single chromatid?

Anaphase II

Which of the following isNOT a characteristic of homologous chromosomes? A) They are similar in size. B) They carry the same alleles for all traits. C) They carry genes for the same traits. D) They are similar in shape and location of the centromere.

B) They carry the same alleles for all traits.

Which of the following would NOT contribute to genetic variation? A) crossing-over of homologous chromosomes B) crossing-over of sister chromatids C) the random alignment of the chromosomes during metaphase I D) the combination of sperm and egg genes

B) crossing-over of sister chromatids

Which of the following is a true statement concerning meiosis in males and females? A) Males provide more genes in sperm than females provide in eggs. B) Crossing-over occurs more often in the formation of sperm than in eggs. C) Spermatogenesis in males results in four functional sperm while oogenesis in females results in only one egg. D) Sperm that contain a recombination of genes are usually more successful in fertilizing an egg.

C) Spermatogenesis in males results in four functional sperm while oogenesis in females results in only one egg.

The following picture depicts which of the following changes in chromosome structure?

Duplication

Which statement is NOT true about homologous chromosomes in meiosis I? A) Homologous chromosomes form tetrads. B) Homologous chromosomes separate and go to different daughter cells. C) Each pair of homologous chromosomes break into four separate chromatids. D) Homologous chromosomes exchange genetic material between nonsister chromatids. E) Homologous chromosomes interact with the spindle as if they were one chromosome.

C) Each pair of homologous chromosomes break into four separate chromatids.

The polar body is...

A nonfunctional cell formed at the same time as an egg cell.

To what does the term chiasma refer?

A structure that holds together homologues during crossing-over

Which of the following accurately describe anaphase I and anaphase II? Select all that apply. A) At the end of anaphase I, each chromosome is composed of two chromatids and at the end of anaphase II, sister chromatids have separated. B) Anaphase I occurs in a haploid cell while anaphase II occurs in a diploid cell. C) Homologous chromosomes separate during anaphase I and sister chromatids separate during anaphase II. D) Anaphase I occurs in both males and females but anaphase II only occurs in females.

A) At the end of anaphase I, each chromosome is composed of two chromatids and at the end of anaphase II, sister chromatids have separated. C) Homologous chromosomes separate during anaphase I and sister chromatids separate during anaphase II.

Identify which event will occur during Prophase I of meiosis but does not occur during prophase of mitosis. A) Bivalents will form. B) Nuclear envelope will dissolve. C) Spindles form as centrosomes migrate away from each other. D) Chromatin will condense into chromosomes.

A) Bivalents will form.

Which of the following statements correctly compares the events of meiosis and mitosis? A) During metaphase I of meiosis, the bivalents are present at the metaphase plate; during metaphase of mitosis, the duplicated chromosomes are at the metaphase plate. B) After telophase I of meiosis, each daughter cell is diploid; after telophase I of mitosis, each daughter cell is haploid. C) During prophase II of meiosis, the homologous chromosomes cross-over; there is no crossing-over during prophase of mitosis. D) During anaphase I of meiosis, the homologues pairs separate; during anaphase of mitosis, the homologous pairs stay together.

A) During metaphase I of meiosis, the bivalents are present at the metaphase plate; during metaphase of mitosis, the duplicated chromosomes are at the metaphase plate.

Which of the following statements is true about the life cycle of animals? A) The gametes are the haploid phase of the animals life cycle. B) The gametes are the diploid phase of the life cycle. C) The products of the haploid phase of the life cycle are larger than those of the diploid phase. D) Meiosis is not a necessary component of the animal life cycle.

A) The gametes are the haploid phase of the animals life cycle.

Dogs have 39 chromosome pairs. Based on this information, determine which of the following statements are true. Select all that apply. A) The haploid number for dogs is 39. B) At the end of mitosis, a cell would have 78 chromosomes. C) At the end of prophase I, a cell would have 78 chromosomes. D) At the end of prophase II, a cell would have 39 chromosomes. E) Meiosis does not occur in dogs.

A) The haploid number for dogs is 39. B) At the end of mitosis, a cell would have 78 chromosomes. D) At the end of prophase II, a cell would have 39 chromosomes.

Which statement applies only to plants? A) The haploid phase can be larger than the diploid phase. B) They use sexual reproduction to produce new offspring. C) They use meiosis in order to produce the gametes. D) They will have a haploid and diploid phase of the life cycle.

A) The haploid phase can be larger than the diploid phase.

Which does NOT occur in meiosis? A) two daughter cells at completion B) four daughter cells at completion C) two nuclear divisions D) formation of bivalents

A) two daughter cells at completion

Another name for a tetrad is a(n)...

Bivalent

Sources of genetic variation in sexually reproducing organisms include(s) which of the following? A) crossing-over in prophase I of meiosis B) independent assortment in metaphase I of meiosis C) fertilization D) All of the choices are sources of genetic variation. E) None of the choices are sources of genetic variation.

D) All of the choices are sources of genetic variation.

Which of the following is/are true about sexual reproduction? A) Gametes are the only haploid phase of the human life cycle. B) The production of gametes is known as gametogenesis. C) A fertilized egg is known as a zygote. D) All of the choices are true. E) None of the choices are true.

D) All of the choices are true.

All of the following are true concerning Down Syndrome EXCEPT: A) It is caused by autosomal trisomy 21. B) In 23% of cases, the sperm contributes the extra chromosome. C) It is the most common trisomy in humans. D) Chances of a woman having a child with Down syndrome decrease as she gets older.

D) Chances of a woman having a child with Down syndrome decrease as she gets older.

Meiosis occurs during which of the following? A) Gametogenesis. B) Oogenesis. C) Spermatogenesis. D) Gametogenesis, oogenesis, and spermatogenesis all involve meiosis. E) None of the answers are correct.

D) Gametogenesis, oogenesis, and spermatogenesis all involve meiosis.

Meiosis accomplishes all of the following EXCEPT A) gamete production. B) reduction of chromosome number (from 2n to n). C) providing genetic variation in sexually reproducing organisms. D) growth and repair.

D) growth and repair.

The cell formed after fertilization of an egg by a sperm is called a(n)...

Zygote