Deck 10: Meiosis and Sexual Life Cycles

Question 1

Which of the following statements about humans is true?

A)The 23rd pair,the sex chromosomes,determines whether the person is female (XX)or male (XY).
B)An ovum and sperm unite during fertilization,forming a haploid (n),single-celled zygote.
C)At sexual maturity,ovaries and testes produce diploid gametes by meiosis.
D)Human life cycles alternate between fertilization and meiosis,with meiosis producing haploid zygotes.

Answer 1

A

Question 2

Which of the following processes leads directly to the formation of gametes in a plant's sexual life cycle?

A)meiosis in the sporophyte
B)mitosis in the gametophyte
C)meiosis in the gametophyte
D)mitosis in the sporophyte

Answer 2

B

Question 3

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

A)The species has 16 sets of chromosomes per cell.
B)Each cell has eight homologous pairs of chromosomes.
C)During the S phase of the cell cycle,there will be 32 separate chromosomes.
D)A gamete from this species has four chromosomes.

Answer 3

B

Question 4

Which of the following statements correctly describes the differences between sexual and asexual reproduction?

A)Asexual reproduction,but not sexual reproduction,is characteristic of all living organisms.
B)In sexual reproduction,offspring vary genetically from their siblings and both parents.
C)In asexual reproduction,offspring are produced by fertilization of sperm and egg.
D)Asexual reproduction produces offspring that vary genetically from the parent.

Question 5

If a sexually reproducing organism has a diploid number of 36,how many individual chromosomes would any of its gametes have?

A)36 chromosomes
B)18 chromosomes
C)72 chromosomes
D)9 chromosomes

Question 6

Which of the following types of organisms has both diploid and haploid forms that exist as separate individuals?

A)animals
B)fungi
C)protists
D)some algae

Question 7

Which of the following is the smallest unit of life that would contain a complete copy of the entire human genome?

A)one human somatic cell
B)one human chromosome
C)one human gamete
D)one human gene

Question 8

Which of the following types of cells would be produced by meiosis?

A)a haploid animal cell
B)a diploid animal cell
C)a diploid plant cell
D)a diploid unicellular organism

Question 9

Which of the following elements do all sexual life cycles in eukaryotic organisms have in common?

A)alternation of generations,gametes,and spores
B)alternation of generations,meiosis,and gametes
C)meiosis,fertilization,and gametes
D)meiosis,gametes,and spores

Question 10

Which of the following statements regarding sexual life cycles is correct?

A)Sexual life cycles can produce both haploid and diploid cells at different stages.
B)Sexual life cycles can produce only haploid cells at different stages.
C)Sexual life cycles can produce only diploid cells at different stages.
D)Sexual life cycles occur only in animals.

Question 11

If a horticulturist breeding plants known as gardenias succeeds in having a single plant with a particularly desirable set of traits,which of the following processes would be her most probable and efficient route to establishing a line of such plants with that particular set of traits?

A)Go back 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.

Question 12

Which of the following statements best describes a karyotype?

A)a pictorial representation of all the genes for a species
B)a display of all 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

Question 13

The somatic cells of a type of shrub called a privet 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)Genes of privet chromosomes are significantly different from those in humans.
C)Privet shrubs must be metabolically more like animals than like other shrubs.
D)Genes on a particular privet chromosome,such as the X,must be on a different human chromosome,such as number 18.

Question 14

What diagnostic procedures can a karyotype be used for?

A)screening for specific genes found in an organism
B)identifying the species of an organism
C)screening for defective or abnormal numbers of chromosomes in an individual
D)identifying the life cycle of a specific organism

Question 15

A given organism has 46 chromosomes in its karyotype.Which of the following statements is correct regarding this organism?

A)It must be human.
B)It must be an animal.
C)It must be sexually reproducing.
D)Its gametes must have 23 chromosomes.

Question 16

In the life cycle of fungi and some protists,which of the following processes leads to the formation of gametes?

A)mitosis in the haploid unicellular or multicellular organism
B)meiosis in the haploid unicellular or multicellular organism
C)meiosis in the diploid zygote
D)mitosis in the diploid zygote

Question 17

Which of the following statements is correct regarding human X and Y chromosomes?

A)They are both present in every somatic cell of males and females alike.
B)They are about the same size and have approximately the same number of genes.
C)They are almost entirely homologous,despite their different names.
D)They are responsible for the determination of an individual's sex.

Question 18

Why are cells arrested at metaphase in the preparation of a karyotype?

A)All of the chromosomes are at their least condensed state and are easy to visualize.
B)All of their chromosomes are highly condensed and easy to visualize.
C)All of the sister chromatids have separated into two new daughter cells.
D)The chromosomes have duplicated,making them easier to visualize.

Question 19

Which of the following statements correctly describes an organism's genome?

A)A genome is a representation of the complete set of polypeptides in any of the organism's cells.
B)A genome is a representation of a single gene locus in an organism.
C)A genome is made up of the genes found in a gamete produced by the organism.
D)A genome is a complete set of all of an organism's genes.

Question 20

Scientists have produced a hybrid plant that was the result of the fertilization of gametes between one plant with a diploid number of 24 and another with a diploid number of 20.How many chromosomes would the diploid hybrid plant have?

A)44 chromosomes
B)22 chromosomes
C)24 chromosomes
D)20 chromosomes

Question 21

Which of the following processes happens during 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.

Question 22

Independent assortment of chromosomes during meiosis is a result of

A)the random and independent way in which each pair of homologous chromosomes lines up at the metaphase plate during meiosis I.
B)the random nature of the fertilization of ova by sperm.
C)the random distribution of the sister chromatids to the two daughter cells during anaphase II.
D)the relatively small degree of homology shared by the X and Y chromosomes.

Question 23

Chromatids are separated from each other during which of the following processes?

A)only during mitosis
B)only during meiosis I
C)only during meiosis II
D)during both mitosis and meiosis II

Question 24

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.

Question 25

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 characteristics are most likely for the two chromosomes of the pair to 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

Question 26

If chiasmata can be seen in a cell under a microscope,which of the following meiotic processes must have occurred?

A)meiosis II
B)anaphase II
C)prophase I
D)anaphase I

Question 27

In a cell undergoing meiosis,if homologous chromosomes are aligned at the equator of the meiotic spindle,what process has occurred?

A)prophase I
B)metaphase I
C)prophase II
D)metaphase II

Question 28

Which of the following events 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)an error in the alignment of chromosomes on the metaphase plate
D)multiple crossover events during meiosis I

Question 29

After telophase II of meiosis,the chromosomal makeup of each daughter cell is

A)diploid,and the chromosomes are each composed of a single daughter chromosome.
B)diploid,and the chromosomes are each composed of two daughter chromosomes.
C)haploid,and the chromosomes are each composed of a single daughter chromosome.
D)haploid,and the chromosomes are each composed of two daughter chromosomes.

Question 30

In a cell undergoing meiosis,if centromeres of sister chromatids become disjoined and chromatids separate,what process has occurred?.

A)metaphase II
B)prophase II
C)prophase I
D)anaphase II

Question 31

If a cell has completed the first meiotic division and is just beginning meiosis II,which of the following statements describes the genetic or chromosomal contents of this cell?

A)It has half the amount of DNA of the cell that began meiosis.
B)It has twice the number of chromosomes.
C)It has half the chromosomes but twice the DNA of the originating cell.
D)It is identical in content to another cell from the same meiosis.

Question 32

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)23
B)46
C)460
D)approximately 8.4 million

Question 33

Which of the following structures is found in a pair of homologous chromosomes?

A)two single-stranded chromosomes that have synapsed
B)two sister chromatids that have synapsed
C)four sister chromatids
D)four unique chromosomes

Question 34

During mitosis or meiosis,sister chromatids are held together by proteins referred to as cohesins.Such molecules must have which of the following properties?

A)They must persist throughout the cell cycle.
B)They must be removed before meiosis can begin.
C)They must be removed before sister chromatids or homologous chromosomes can separate.
D)They must be intact for nuclear envelope re-formation.

Question 35

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

A)chromosome replication
B)synapsis of pairs of homologous chromosomes
C)production of daughter cells
D)condensation of chromatin

Question 36

In a cell undergoing meiosis,if synaptonemal complexes form or are still present,what process or processes have occurred?

A)prophase I only
B)prophase I and telophase I only
C)prophase I and telophase II only
D)prophase I,metaphase I,and anaphase I only

Question 37

The karyotype of one species of primate has 48 chromosomes.In a particular female,cell division malfunctions,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 processes?

A)mitosis in her ovary
B)telophase II of one meiotic event
C)telophase I of one meiotic event
D)either anaphase I or II of meiosis

Question 38

The following question refers to the essential steps in meiosis described below.
1)formation of four new nuclei,each with half the chromosomes present in the parental nucleus
2)alignment of homologous chromosomes at the metaphase plate
3)separation of sister chromatids
4)separation of the homologs;no uncoupling of the centromere
5)synapsis;chromosomes moving to the middle of the cell in pairs
Which of the steps take(s)place in both mitosis and meiosis?

A)3
B)5
C)2 and 3 only
D)2,3,and 5

Question 39

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 half the number of chromosomes and half the amount of DNA.
B)They have the same number of chromosomes and half the amount of DNA.
C)They have half the number of chromosomes and one-fourth the amount of DNA.
D)They have half the amount of cytoplasm and twice the amount of DNA.

Question 40

To visualize and identify meiotic cells at metaphase I with a microscope,what would you look for?

A)sister chromatids of a replicated chromosome grouped at the poles
B)individual chromosomes all at the cell's center
C)an uninterrupted spindle array
D)pairs of homologous chromosomes all aligned at the cell's center

Question 41

Refer to Figure 10.6 above.Which of the progression of events listed corresponds to the series of events that occurs in the life cycle of animals?

A)zygote,mitosis,gametophyte,mitosis,fertilization,zygote,mitosis
B)diploid multicellular organism,meiosis,fertilization,zygote,mitosis
C)fertilization,mitosis,multicellular haploid,mitosis,spores,sporophyte
D)gametophyte,meiosis,zygote,spores,sporophyte,zygote

Question 42

If the DNA content of a diploid cell in the G₁ phase of the cell cycle is 24 fg (femtograms),then the DNA content of the same cell at metaphase of meiosis II would be

A)12 fg.
B)6 fg.
C)24 fg.
D)48 fg.

Question 43

In a life cycle such as that shown in diagram II of Figure 10.6 above,if the zygote's chromosome number is 10,which of the following will be true?

A)The sporophyte's chromosome number per cell is 10,and the gametophyte's is 5.
B)The sporophyte's chromosome number per cell is 5,and the gametophyte's is 10.
C)The sporophyte and gametophyte each have 10 chromosomes per cell.
D)The sporophyte and gametophyte each have 5 chromosomes per cell.

Question 44

A human cell containing 22 autosomes and a Y chromosome is

A)a sperm.
B)an egg.
C)a zygote.
D)a somatic cell of a male.

Question 45

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

A)All eggs will have paternal types of gene combinations.
B)Half the eggs will have maternal and half will have paternal combinations.
C)Each egg has a one-fourth chance of having blue long,blue short,orange long,or orange short combinations.
D)Each egg has a three-fourths chance of having blue long,one-fourth blue short,three-fourths orange long,or one-fourth orange short combinations.

Question 46

Which of the following statements correctly describes the characteristics of recombinant chromosomes?

A)They carry genes from only one parent.
B)They contain more genes than non-recombinant chromosomes.
C)At least one to three times per chromosome pair,they carry genes from two different parents.
D)They are identical in genetic makeup to the parental chromosomes.

Question 47

You have isolated DNA from three different cell types of an organism,determined the relative DNA content for each type,and plotted the results on the graph shown in the figure above.Which sample(s)of DNA might be from a cell at the end of anaphase II of meiosis?

A)III
B)II
C)either I or II
D)both I and II

Question 48

You have isolated DNA from three different cell types of an organism,determined the relative DNA content for each type,and plotted the results on the graph shown in the figure above.Which sample(s)of DNA might be from a germ cell arrested in prophase I of meiosis?

A)I
B)II
C)either I or II
D)both I and II

Question 49

When homologous chromosomes cross over,what is the result?

A)Two sister chromatids get tangled,resulting in one altering the sequence of its DNA.
B)Two sister chromatids exchange identical pieces of DNA.
C)Specific proteins break the two strands of nonsister chromatids and re-join them.
D)Each of the four DNA strands of a homologous pair is broken,and the pieces are mixed.

Question 50

Which phase of meiosis is represented in the figure above?

A)metaphase I
B)anaphase II
C)prophase I
D)metaphase II

Question 51

Figure 10.6
Refer to the life cycles illustrated in Figure 10.6 above.Which of the life cycles is (are)typical for animals?

A)I only
B)II only
C)III only
D)I and II

Question 52

If the DNA content of a diploid cell in the G₁ phase of the cell cycle is 24 fg (femtograms),then the DNA content of the same cell at metaphase of meiosis I would be

A)12 fg.
B)6 fg.
C)24 fg.
D)48 fg.

Question 53

Homologous chromosomes move toward opposite poles of a dividing cell during

A)mitosis.
B)meiosis I.
C)meiosis II.
D)fertilization.

Question 54

There is a group of invertebrate animals called rotifers,among which a particular group of species reproduces,as far as is known,only asexually.These rotifers,however,have survived a long evolutionary history without evidence of having been overcome by excessive mutations.Because the rotifers develop from eggs,but asexually,what can you predict about these organisms?

A)The eggs and the zygotes are all haploid.
B)The animals are all males.
C)Although asexual,both males and females are found in nature.
D)No males can be found.

Question 55

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 above.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?

A)either two number 12 chromosomes with blue genes or two with orange genes
B)either two number 19 chromosomes with long genes or two with short genes
C)either one blue or one orange gene in addition to either one long or one short gene
D)one chromosome 12 with one blue gene and one chromosome 19 with one long gene

Question 56

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 above.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?

A)only blue short gene eggs
B)only orange short gene eggs
C)one-half blue short and one-half orange short gene eggs
D)three-fourths blue short and one-fourth orange short gene eggs

Question 57

Refer to the life cycles illustrated in Figure 10.6 above.Which of the life cycles is (are)typical for plants and some algae?

A)I only
B)II only
C)III only
D)I and II

Question 58

During which process does independent assortment of chromosomes occur?

A)during mitosis only
B)during meiosis I only
C)during meiosis II only
D)during mitosis and meiosis I

Question 59

Which phase of meiosis is represented in the figure above?

A)anaphase I
B)anaphase II
C)prophase I
D)telophase I