Chapter 7

Which of the following is true during meiosis? a. each gamete receives two alleles for each gene from only one parent b. each gamete receives one allele for each gene from each parent c. each gamete receives two alleles for each gene from each parent d. each gamete receives a random number of alleles for each gene from each parent

The law of independent assortment states that ____________. a. inheritance of a specific gene is not influenced by other genes b. genes that are further apart will be less likely to be inherited together c. each gamete receives one allele for each gene from each parent d. genes that are on the same chromosome are inherited together

According to Mendel's Law of Dominance, the phenotype of a heterozygote will be ____________. a. determined by the dominant allele b. determined by the mother's genotype c. determined by the recessive allele d. a mixture of the phenotypes of both parents

During what process do homologous chromosomes segregate into different gametes? a. meiosis b. cytokinesis c. DNA synthesis d. DNA replication

Which law of inheritance is incorrectly matched to its explanation? a. law of dominance; in a heterozygote individual, only the dominant allele will influence the phenotype b. law of independent assortment; inheritance of one gene does not influence inheritance of another gene c. law of segregation; each gamete receives both copies of gene from its parent d. law of segregation; each gamete receives only on copy of each gene from its parent

In a dihybrid cross of seed color and seed shape, Y (yellow) is dominant to y (green) and R (rounded) is dominant to r (wrinkled). An individual with genotype YyRr is crossed with an individual with genotype YYRr. The inheritance of the alleles for seed color does not affect inheritance of genes for seed shape. Which law supports this statement? a. law of dominance b. law of independent assortment c. law of random mating d. law of segregation

When a cell's DNA has become damaged beyond repair, the cell undergoes which of the following processes? a. exocytosis b. photosynthesis c. apoptosis d. glycolysis e. endocytosis

During what state of the cell cycle would you expect to have the lowest amount of cellular growth and synthesis taking place? a. the G2 phase b. the G1 phase c. the S phase d. the M phase

Which of the following describes cell activity during the G1 phase of the cell cycle? a. the cell is in a resting phase b. the cell increases the size and produces the new organelles c. DNA is replicated d. the cell undergoes mitosis

Which of the following phases of the cell cycles make up what is known as interphase? a. G1, S, and M b. M, S, and G2 c. G1, G2, and M d. G1, S, and G2

Central nervous system nerve cells spend most of their lives in which of the following phases of the cell cycle? a. G2 b. S c. G1 d. G0

The checkpoint at the end of which phase is considered the most important aspect of the cell cycle regulation, as any potential problems with it can lead to cancer? a. S b. G1 c. M d. G2

Which phase of the ell cycle involves DNA replication? a. the S phase b. the M phase c. the G2 phase d. the G1 phase

What is the purpose of the G1 phase of the cell cycle? a. no purpose has yet been characterized b. growth and replication of the organelles c. formation of the mitotic spindle d. DNA synthesis

How many chromosomes are present in a human somatic cell during the G2 phase? a. 23 b. 92 c. 46 d. 108

Which of the following steps is irreversible in the cell cycle? I. transition from prophase to metaphase II. sister chromatid separation III. DNA replication a. II only b. I only c. II and III d. I and III

How is metaphase of mitosis defined? a. chromosomes move towards the center or equator of the cell; chromatids have not separated b. two distinct cells begin to form and separate from one another c. DNA begins to replicate d. centrioles begin to move towards opposite poles of the cell

During which phase of mitosis do sister chromatids separate? a. anaphase b. prophase c. metaphase d. telophase

During which phase of mitosis do chromatids condense? a. prophase b. metaphase c. telophase d. anaphase

Which of the following actions occurs during telophase of mitosis? a. the nucleolus dissolves b. nuclear membranes dissolve c. cytokinesis d. chromosomes line up at the center of the cell

During which phase of the cell cycle s the nuclear envelope not intact? a. S phase b. anaphase c. early prophase d. telophase e. G1 phase

Chromatid separation is associated with what phase of mitosis? a. metaphase b. anaphase c. telophase d. prophase

Which choice properly matches the stage of mitosis with its description? a. prophase: pairs of chromosomes line up along the center of the cell b. anaphase: chromatin condenses, and a structure made up of microtubules forms c. metaphase: chromosome pairs separate and migrate to opposite ends of the cell, propelled by the shortening mitotic spindle d. anaphase: chromosomes replicate and the cell proceeds through multiple pre-mitotic checkpoints e. telophase: two new nuclei form, each containing a group of migrates chromosomes

What is a centromere? a. a protein made mostly of tubulin b. the site of association of sister chromatids c. an organelle that organizes microtubules d. a protein that holds sister chromatids together

The mature form of a newly discovered species of eukaryote contains 12 chromosomes and exists in the diploid state. In this new species, how many chromosomes are present in a mitotic cell immediately after the sister chromatids have separated? a. 24 b. 6 c. 18 d. 12

Presence of nuclear membrane indicates that the cell is in which of the following phases? a. metaphase b. interphase c. telophase d. prophase

During which of the following mitotic phases will a cell be haploid? a. none of these b. anaphase c. metaphase d. prophase

Human somatic cells have 46 chromosomes. How man chromosomes are present in a human cell during metaphase of mitosis? a. 92 b. 23 c. 46 d. 184

Which of the following processes occurs during anaphase of mitosis? a. the cell briefly contains 92 chromosomes b. centrioles separate c. chromosomes decondense d. DNA is synthesized

In which stage of mitosis do the chromosomes line up along the equatorial plate? a. prophase b. anaphase c. metaphase d telophase

In animal cells, the process of cytokinesis occurs due to which of the following factors? a. the sliding of microtubules near the center of the cell b. the movement of spindle fibers c. the sliding of microtubules around the circumference of the cell d. actin filaments contracting around the circumference of the cell

In chemotherapy, it is common to use drugs that can stabilize or depolymerize microtubules. Of the following statements, which is correct about these drugs? a. the drugs disrupt tumor movement b. the drugs disrupt mitosis c. the drugs disrupt endocytosis processes d. the drugs disrupt the condensation of chromosomes

Which of the following is the total number of chromosomes in somatic cells and gametes, respectively? a. Somatic cells have 23 chromosomes and gametes have 23 b. Somatic cells have 46 chromosomes and gametes have 23 c. Somatic cells have 23 chromosomes and gametes have 46 d. Somatic cells have 46 chromosomes and gametes have 46 e. Somatic cells have 20 chromosomes and gametes have 30

Which of the following does not occur during mitosis? a. Crossing over b. Separation of the sister chromatids c. Maintenance of ploidy d. Formation of two identical daughter cell

Which of the following occurs during prometaphase stage of mitosis? a. The chromosomes move to different poles of the cell b. Chromosomes line up at the metaphase plate c. The nuclear membrane breaks down d. Chromosomes condense

What is the arrangement of microtubules that make up a centriole? a. Nine triplets b. Nine pairs plus one pair in the center c. Nine microtubules d. Nine pairs

Where does a microtubule from the mitotic spindle attack to a sister chromatid? a. Centriole b. Centrosome c. Kinetochore d. Kinesin

What is the composition of the contractile ring that forms during cytokinesis? a. Myosin and actin b. Myosin only c. Myosin, actin, and kinesin d. Actin only

During mitosis, which protein motor is involved in moving sister chromatids to opposite poles of the dividing cell? a. Myosin b. Kinesin c. Dynein d. Prestin

Which of the following is true of the two daughter cells formed during mitosis? a. They are genetically identical to the parent cell b. They are half the size of the parent cell c. Daughter cells contain only newly synthesized genetic material d. One daughter cell is larger than the other

What is the role of centrosomes in mitosis? a. Separation of chromosomes to opposite poles b. To aid in cytokinesis c. Arrangement of sister chromatids at the metaphase plate d. Organization of microtubules

d. 16

A cell undergoing mitosis contains sixteen chromosomes lined up at the metaphase plate. How many total chromatids will each of the daughter cells receive after the correct completion of cell division? a. 16 b. 4 c. 32 d. 8

d. To maintain structure of the chromosome and assist in controlling the activity of the genes

Kinetochores fibers form in which phase of mitosis? a. Prometaphase b. Metaphase c. Prophase d. Anaphase

What does "n" mean when one says that cells are "2n" or "n"? a. "n" refers to the amount of nuclei in the cell. b. "n" refers to the amount of chromosomes in a cell. c. "n" refers to the amount of nitrogen in the DNA of cells. d. "n" refers to the number of daughter cells a cell can produce. e. "n" refers to the amount of chromosome copies in a cell.

During which of the following phases will a human somatic cell contain the least amount of DNA? a. G2 phase b. Prophase c. G1 phase d. Metaphase

Histones, molecules that package DNA into nucleosomes, are mostly made up of _____________. a. nucleotides b. monosaccharides c. fatty acids d. amino acids

The cell cycle has many checkpoints to ensure the cell is ready for division. Which of the following can occur if a cell skips cell cycle checkpoints? a. The cell can grow in size, but never divide b. None of these could occur c. The cell can have inhibited growth d. The cell can become cancerous e. The cell can divide into three daughter cells instead of two

During cellular interphase, DNA appears to have regions of tight winding within its strands. This gives the appearance of "beads" within the DNA. Which of the following forms the "beads" seen during interphase? a. Nucleosomes b. Nucleoids c. Heterochromatin d. Histone tails e. Looped domains

The accumulation of cyclin protein results in which of the following? a. Degradation of cyclin-dependent kinases b. Completion of DNA synthesis c. Progression through cell cycle checkpoints d. Growth factor synthesis

A developing cell can pass the G1 checkpoint in the cell cycle if sufficient conditions are present for its further growth. This process is regulated by a number of proteins, including cyclins and their associated kinases. Imagine that a cell is arrested at the G1 checkpoint and never proceeds further. Which of these statements properly describes the situation? a. The cell has already replicated its chromosomes, but will not enter mitosis b. The cell has not yet replicated its chromosomes, and will not be able to do so because it cannot enter the S phase c. The cell has already undergone prophase of mitosis, but will not enter metaphase d. The cell has already replicated its chromosomes, but will not proceed into the S phase

What is the restriction point? a. A decision point in mitosis; if the restriction point is passed mitosis will progress b. A decision point in the cell cycle; if the restriction point is passed the cell cycle will progress to the next phase c. A decision point in mitosis; if the restriction point is passed mitosis will not progress d. A decision point in the cell cycle; if the restriction point is passed the cell cycle will not progress to the next phase

A scientist takes a sample of human epithelial cells, injects it with a dye that highlights the genetic information, and places the sample under the microscope. What will the genetic information for the majority of the cells look like? a. Condensed into 23 discrete chromosomes and restricted to the nucleus b. Condensed into 46 discrete chromosomes and restricted to the nucleus c. Condensed into a single circular chromosome and floating in the cytoplasm d. Condensed into 23 discrete chromosomes and floating in the cytoplasm e. Uncondensed and restricted to the nucleus

Which of the following terms refers to all of the changes that occur within a cell? a. Synthesis b. Homeostasis c. Biochemistry d. Metabolism e. Replication

Which of the following is the shortest part of the cell cycle? a. Mitosis b. S phase c. G1 phase d. Interphase e. G0 phase

The regulatory subunit of maturation-promoting factor __________. a. converts ADP to ATP b. is called cyclin because its concentration rises and falls predictably as the cell cycle progresses c. transfers a phosphate group to certain serine and threonine residues of specific protein substrates d. converts ATP to ADP e. removes a phosphate group from certain tyrosine residues of specific protein substrates

Which of the following does not regulate cyclin-dependent kinases (CDK's) to influence a cell's progress through the cell cycle? I. Cyclin concentration II. CDK phosphorylation/ unphosphorylation III. Subcellular localization IV. Controlled cell lysis a. I, II, III, and IV b. I, II, and III c. II only d. I and II e. IV only

Which of the following is a trait unique to cancer cells? a. They communicate with other cells through chemical signaling b. They have escaped form cell cycle controls and inhibitions c. They do not use glucose as an energy source d. Density-dependent growth factors limit their division e. They do not undergo interphase

Which of the following terms is used to describe programmed cell death? a. Caspases b. Anaphase c. Procaspases d. Apoptosis e. Necrosis

A scientist is interested in studying the event of crossing over (recombination) in mouse gametes. She wants to label some of the mouse DNA with fluorescent dyes to better visualize it. During what phase of the cell cycle should she look at these fluorescent DNA strands in order to most effectively study recombination? a. Metaphase II b. Prophase I c. Anaphase II d. Telophase I e. Anaphase I

Which of these statements is FALSE concerning mitosis and meiosis? a. Meiosis results in a halving of chromosomes in the daughter cells, while mitosis reserves the same amount of genetic material in the daughter cells. b. Both processes require DNA synthesis beforehand. c. Both use the same order of events: prophase, metaphase, anaphase, and telophase. d. Both of these processes allow genetic variationd.

Which of the following highlights a key difference between meiosis and mitosis? a. Genetic mutations can only occur in meiosis; mitosis always results in identical daughter and parent cells b. All answer choices are correct c. Meiosis involves two divisions, while mitosis involves only one d. There is no metaphase stage in meiosis

Which of the following statements regarding mitosis and meiosis is correct? a. Mitosis only occurs in prokaryotes, including all bacteria, while meiosis occurs in higher life forms b. Mitosis results in higher genetic variability than meiosis c. In the human body, mitosis occurs in somatic cells while meiosis occurs in sex cells d. None of the other answer choices are correct

Which of the following chromosomal abnormalities is an example of monosomy? a. Down syndrome b. Klinefelter syndrome c. Edwards syndrome d. Turner syndrome

Non-disjunction can result in which of the following? a. Monosomy b. Both monosomy and trisomy c. Neither monosomy, nor trisomy can be caused by non-disjunction d. Trisomy

Which of the following would result in a cell with an abnormal number of chromosomes after meiosis? a. Separation of sister chromatids b. Cleavage of the securin protein c. Nondisjunction d. Recombination

Crossing over is an event that contributes to the non-identical nature of gametes. Which of the following is true regarding crossing over? I. It occurs during prophase I II. It involves exchange of genetic material between sister chromatids III. It involves exchange of genetic material between homologous chromosomes a. I b. I and II c. I and III d. II

Independent assortment of traits on different chromosomes is due to the random alignment of different pairs of homologues. This alignment occurs during which of the given phases? a. Prophase I b. Metaphase II c. Metaphase I d. Prophase II

Which of the following is true regarding meiosis I and meiosis II? a. Sister chromatids separate in anaphase of meiosis I, but not in meiosis II b. Both produce haploid cells c. Both involve reductional division d. The G2 phase precedes both

In vertebrates, sperm cells typically contribute which of the following a new organism? a. A complementary haploid portion of chromosomes b. All of the cytoplasm of the zygote c. Diploid sex chromosomes d. A complete zygote e. Nuclei

Of the following choices, which most accurately describes the cells produced from the process of meiosis? a. The cells are genetically unique from the parental cells b. The cells are genetically identical to all other cells in the human body c. The cells are used in the repair of tissues d. The cells are diploid e. The cells are genetically identical to the parental cells

Which of the following is a way in which meiosis increases genetic diversity? a. Separation of sister chromatids b. Inducing genetic mutations c. Chromosome condensation d. Recombination

In multicellular eukaryotes, there are two distinct cell types: germ cells and somatic cells. Which of the following is characteristic of germ cells? a. They are a special type of somatic cell b. They produce gametes c. They are haploid d. They only undergo mitosis e. They only undergo meiosis

A scientist is dissecting a female fetal pig and takes a tissue sample from its ovaries. The scientist places the tissue sample on a slide and examines the eggs in the ovarian tissue. At what stage in the cell cycle are these germ cells? Assume that oogenesis in the fetal pig is the same as in a human. a. Anaphase I b. Prophase I c. Prophase II d. Metaphase I e. Metaphase II

When would the creation of a Down Syndrome gamete occur? a. Telophase II b. Prophase I c. Anaphase I d. Metaphase II

Which of the following statements is true concerning meiosis? a. Cells are diploid at the end of meiosis I b. During metaphase II, tetrads align at the equator of the cell c. Recombination occurs only during metaphase I d. Daughter cells are haploid at the conclusion of both meiosis I and meiosis II e. Daughter cells are still genetically equivalent after meiosis I

Why is there a reduction of ploidy after meiosis I? a. Sister chromatids are separated and placed in unique daughter cells b. Reduction of ploidy only occurs after mitosis c. Pairs of homologous chromosomes are separated and placed in unique daughter cells d. The two daughter cells after meiosis I each contain only half of the original cytoplasm e. Reduction of ploidy only occurs after meiosis II

Which of the following is a correct statement about the difference between meiosis and mitosis? a. Mitosis produces two identical, diploid daughter cells after one division; meiosis produces four non-identical, haploid daughter cells after two divisions b. Mitosis produces two identical, haploid daughter cells after one division; meiosis produces four non-identical, diploid daughter cells after two divisions c. Mitosis produces two identical, diploid daughter cells after two divisions; meiosis produces four non-identical, haploid daughter cells after one division d. Mitosis produces four identical, diploid daughter cells after one division; meiosis produces two non-identical, haploid daughter cells after two divisions e. Mitosis produces two non-identical diploid daughter cells after one division; meiosis produces four identical, haploid daughter cells after two divisions

During which phase of meiosis does chiasmata occur? a. Metaphase I b. Anaphase II c. Anaphase II d. Prophase I e. Prophase II

A human cell has 44 chromosomes and two X chromosomes. It is __________. a. a gamete from a female b. a somatic cell from a male c. an ovum d. a somatic cell from a female e. a sperm

Meiosis in animals occurs in __________. a. testes only b. both ovaries and testes c. all cells in the animal's body d. all somatic cells e. ovaries only

What would happen if gametes were made by mitosis instead of meiosis? a. Each generation of cells would have 23 chromosomes b. With each generation, the number of chromosomes in each cell would double c. Each generation of cells would have 44 chromosomes d. Each generation of cells would have 46 chromosomes e. More than one of these

Diploid cells contain how many times more chromosomes than haploid (n) cells? a. The same amount (n) b. Three times as many (3n) c. Twice as many (2n) d. Four times as many (4n)

What is the cell division error that causes trisomy 21, or Down syndrome? a. Organelle partitioning b. Telomere shortening c. Nucleotide deletion d. Nondisjunction

Which molecular mechanism is not a possible cause of nondisjunction? a. Maternal gametes have a higher chance of exhibiting nondisjunction b. Error in cytoplasmic partitioning c. Failure to pass the spindle assembly checkpoint d. Older age of an individual leads to weaker cohesion complexes at the centromere

Which of the following organisms do not perform meiosis? a. Bacteria b. Mosses c. Mammals d. Flowering plants

What enzyme aids in chromosomal crossing over during prophase I of meiosis? a. Recombinase b. Protein kinase c. DNA polymerase d. DNA ligase

What is the term for the structural arrangement of chromatids undergoing crossing over during meiosis? a. Holliday junction b. Kinetochore c. Equatorial plane d. Telomere

What is the sex determination system in humans? a. ZW system b. XX/XO system c. Temperature-dependent system d. XX/XY system

What are examples of sex chromosome disorders? a. Klinefelter's syndrome only b. Trisomy 21 only c. Turner syndrome and trisomy 21 d. Klinefelter's syndrome and Turner syndrome

Do sex chromosomes undergo crossing over? a. Yes, sex chromosomes undergo crossing over, but only in a small region of homology. b. No, sex chromosomes do not undergo crossing over due to a need of sex-specific gene conservation. c. Yes, sex chromosomes undergo normal crossing over. d. No, sex chromosomes do not undergo crossing over due to a lack of homology.

During the process of crossing over, what aids in the repair of DNA double stranded breaks? a. Invading chromatid DNA strand b. Primase c. Complementary DNA strand d. DNA polymerase

What is a method through which meiosis generates genetic diversity? a. Crossing over and independent assortment b. Mitotic spindle interference and crossing over c. Independent assortment only d. Crossing over only

What chemical feature of DNA allows for the crossing over event during meiosis? a. Mutation b. Hydrogen bonds between DNA strands c. Mismatched base pairs d. Double-stranded breaks

Where in the human body are the cells that undergo meiosis located? a. Bone marrow b. All cells can undergo meiosis c. Small intestine d. Gonads

Synapsis allows which of the following to occur? a. The shortening of the mitotic spindles b. Chromosome condensation c. Nuclear membrane dissolution d. Crossing over

What cellular features are duplicated during prophase II of meiosis? a. Centrosomes b. Centrioles c. Plasma membrane d. Genetic material

Which of the following is not true of human gametes? a. They are haploid b. Male and female gametes fuse during fertilization c. They arise from somatic cell lines d. Gametes are produced during meiosis

d. The resulting number of chromosomes per cell

In regards to DNA, how does a cell prepare for cell division? DNA is __________ to create two __________ per __________, which are connected at the __________. a. replicated . . . sister chromatids . . . chromosome . . . centromere b. replicated . . . homologous chromatids . . . chromosome . . . centriole c. replicated . . . homologous chromosomes . . . chromatid . . . centromere d. replicated . . . homologous chromosome . . . chromatid . . . centriole e. replicated . . . sister chromosomes . . . chromatid . . . centromere

b. Mitosis contributes to genetic diversity in sexual organisms c. Mitosis allows for repair of damaged tissues d. All of these are functions of mitosis e. Mitosis is the process by which asexual organisms reproduce

e. mitosis . . . ovum . . . unequal division of cytoplasm

Which of the following cells will undergo meiosis? a. Amoebae b. Germ cells c. All of these d. Heart cells e. Unicellular organisms