Chapter 8 Biology

At the start of mitotic anaphase,

the centromeres of each chromosome come apart.

Cancer is not usually inherited because

the chromosomal changes in cancer are usually confined to somatic cells

Which of the following statements regarding sexual and asexual reproduction is true?

Sexual reproduction is more likely to increase genetic variation than is asexual reproduction.

Which of the following types of organisms commonly demonstrates polyploidy?

flowering plants

A karyotype is most like

photographs of every couple at a high school prom.

A duplicated chromosome is being represented. What structure is represented by my waist, where I am joined with my twin?

centromere

A benign tumor differs from a malignant tumor in that a benign tumor

does not metastasize.

The phase of mitosis during which the mitotic spindle begins to form is

prophase

During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur?

prophase 1

The correct order of events during meiosis is

prophase 1, metaphase 1, anaphase 1, telophase 1, cytokinesis, meiosis 2

During which stage of meiosis do synapsis and crossing over occur?

prophase I

Which of the following statements regarding mitosis and meiosis is false?

Meiosis provides for asexual reproduction.

Which of the following statements regarding the cell cycle control system is false?

The cell cycle control system operates independently of the growth factors.

Meiosis starts with a single diploid cell and produces

four haploid cells.

Jacobsen syndrome, which can cause heart defects, intellectual deficiencies, and bleeding disorders, is caused by a deletion of the terminal end of chromosome 11. What method could you use to determine whether an individual has Jacobsen syndrome?

Perform a karyotype using a person's white blood cells.

Which of the following features likely accounts for the difference between plant and animal cell cytokinesis?

Plant cells have cell walls.

Which of the following statements is false?

An X chromosome is an autosome.

Which of the following statements regarding the differences between mitosis and meiosis is false?

Crossing over is a phenomenon that creates genetic diversity during mitosis.

Which of the following statements about nondisjunction is false?

In mammals, extra copies of the Y chromosome are typically inactivated.

Which of the following statements regarding mitosis and meiosis is false?

Mitosis produces daughter cells with half the number of chromosomes as the parent cell.

Which of the following statements regarding prokaryotes is false?

Prokaryotic chromosomes are more complex than those of eukaryotes.

A pair of sex chromosomes found in a human male is most like

a bride and groom.

Which of the following shows the greatest promise as a cancer chemotherapy agent?

a drug that prevents mitotic spindle from forming

Drag the labels onto the diagram to identify the stages of the life cycle. Not all labels will be used.

a. gamates b. haploid c. meiosis d. fertilization e. diploid f. zygote g. mitosis

Drag the pink labels onto the pink targets to identify key events in mitosis. Then drag the blue labels onto the blue targets to identify the stages of mitosis.

a. mitotic spindle forming b. sister chromatids centered c. chromosomes separating d. nuclear envelopes forming e. interphase f. prophase g. metaphase h. anaphase i. telophase and cytokenesis

Drag the labels onto the diagram to identify the various chromosome structures.

a. pair of homologous chromosones b. centremere c. sister chromatids

Strictly speaking, the phrase "like begets like" refers to

asexual reproduction only.

The creation of genetically identical offspring by a single parent, without the participation of sperm and egg, is called

asexual reproduction.

As a patch of scraped skin heals, the cells fill in the injured area but do not grow beyond that. This is an example of

density-dependent inhibition.

Which of the following is a feature of plant cell division that distinguishes it from animal cell division?

formation of cell plate

During prophase I of meiosis,

homologous chromosomes stick together in pairs.

A cell preparing to undergo meiosis duplicates its chromosomes during

interphase

Nondisjunction occurs when

members of a chromosome pair fail to separate

During which phase of mitosis do the chromosomes line up on a plane equidistant from the two spindle poles?

metaphase

Which of the following helps maintain the structure of chromosomes and control the activity of genes?

proteins

Independent orientation of chromosomes at metaphase I and random fertilization are most like

shuffling cards and dealing out hands of poker.

What stage of the life cycle must the cell be in?

the start of meiosis I

Imagine you found an organism. You examined one of its gametes and you see that it contains 5 chromosomes. How many chromosomes will one of its body cells contain just before mitosis begins?

10

Which of the following statements correctly describes the behavior of a tetrad during anaphase I of meiosis?

It splits into two pairs of sister chromatids, and one pair goes to each pole of the dividing cell.

Drag the labels to the correct locations on these images of human chromosomes.

a. homologous chromosomes b. centromere c. sister chromatids d. autosomes e. sex chromosomes f. karyotype

Can you organize these terms that describe the different kinds of cell division?

a. mitosis b. meiosis c. asexual reproduction d. somatic cells e. gametes f. sexual reproduction

Drag the labels onto the grid to indicate the phases of mitosis and meiosis. Use only pink labels for pink targets.

a. mitosis b. prophase c. metaphase d. anaphase, telophase, cytokenesis e. meiosis f. prophase 1 g. metaphae 1 h. anaphase 1, telophase 1, cytokenesis i. meiosis 2

If a chromosome fragment breaks off and then reattaches to the original chromosome but in the reverse direction, the resulting chromosomal abnormality is called a(n)

an inversion

Eukaryotic chromosomes differ from prokaryotic chromosomes in that they

are housed in a membrane-enclosed nucleus.

___________reproduction is a means of creating new individuals solely by ________, the form of cell division that creates genetically identical daughter cells. _________reproduction, in contrast, generates genetically unique offspring. To accomplish this, an organism must produce_________-- sperm and egg -- through the process of _______. The cells produced this way will be _______, meaning that they contain a single set of chromosomes. Such cells are produced only in the ________.

asexual mitosis sexual gametes meiosis haploid gonads

Two chromosomes in a nucleus that carry genes controlling the same inherited characteristics are

homologous chromosomes.

At a chiasma, two ________ are attached to each other.

homologous or nonsister chromatids

If you look through a microscope and see a cell with chromosomes lined up two by two which cellular reproduction stage would you be looking at?

meiosis I only

Of the 2 cell division's we learned, which process is going on in your hand right now?

mitosis

Which of the following is probably the main factor responsible for the phenomenon of density-dependent inhibition?

physical contact of cell-surface proteins between adjacent cells

A cell that has a cell wall is undergoing cell division, and the following events are observed: the formation of a cell plate and the division of the cell into two daughter cells. What type of cell is being observed and what process(es) is it going through?

plant cell; telophase and cytokinesis of mitosis

During which phase of mitosis does the nuclear envelope re-form?

telophase