BIO-110 CH 11-12

Mouse cells have 40 total individual chromosomes. Therefore, they have __________homologous chromosome pairs.

20

Including the sex chromosomes, the chromosome number of a normal human cell is______and the chromosome number of this HeLa cell is______

23, 23

Which of the following best describes metaphase of mitosis?

Chromosomes line up along the equatorial plate

Which of the following is NOT true of crossing over?

Crossing over can occur only once per pair of homologous chromosomes.

Which of the following is defined as the process of a cell dividing into two daughter cells?

Cytokinesis

Which of the following best describes the process of DNA replication in eukaryotes?

DNA replication always proceeds in a 5' to 3' direction.

If a diploid organism's somatic cells have thirty-six chromosomes, how many chromosomes would its haploid gametes have?

Eighteen

Which terms typically apply to eukaryotic chromosomes? Select all that apply.

Found in nucleosomes Linear Multiple origins of replication

The interval of cell growth before DNA replication The time of DNA replication The interval when the cell prepares to divide

G1 S G2

The following images represent the total chromosome number for a cell. Select whether each image represents a haploid or a diploid cell.

Haploid (n)

The concept that the distribution of one chromosome does not affect the distribution of any other chromosome during meiosis is known as which of the following?

Independent assortment

Which of the following is not a phase of mitosis?

Interphase

What sex is the normal human karyotype displayed here?

Male

During which stage of mitosis are the chromosomes aligned midway between the spindle poles?

Metaphase

__________ is a nuclear division mechanism that maintains the________________

Mitosis, chromosome number

Which of the following is NOT an example of fail-safe mechanisms that prevent the irregular cell divisions characteristic of cancer?

Mutation in a tumor suppressor gene

Which of the following demonstrates the link between oncogenes and cancer?

Oncogenes do not have mutations that increase the activity or number of molecules that stimulate mitosis.

Which of the following is a stage of mitosis? Select all that apply.

Prophase Telophase Anaphase Metaphase

During which phase of meiosis do homologous chromosomes form pairs?

Prophase I

Which phase of interphase is characterized by a period of cell growth and the production of molecules for DNA replication?

S

Without warning, something changes in the environment of both of these populations. The climate shifts suddenly, creating hotter weather for longer periods of time. This change puts individuals with long fur at serious risk of overheating. What do you predict will happen?

Since the southern population has greater variation within the population, some individuals will survive while others will die out.

Which of the following best describes anaphase II of meiosis?

Sister chromatids are pulled apart.

Which of the following cells would be an example of a somatic cell in a diploid organism?

Skin cell

Which of the following is true for both meiosis and mitosis?

The genome is duplicated before mitosis or meiosis occurs.

Which of the following are characteristics of benign tumors? Select all that apply.

They are slow growing. They stay in their home tissue.

Which group of mice showed the most meiotic abnormalities in their oocytes?

Those in damaged cages with damaged plastic water bottles

For most multicelled organisms, the somatic cells (all the cells in the body except the gametes) are diploid (represented by the symbol 2n). In other words, the somatic cells all carry two (a homologous pair) of each chromosome. Because an organism, in most cases, can have multiple possible versions of the same gene, the genes in homologous chromosomes might be slightly different from one another. These different gene versions are called _________. When an organism only has one version of each individual chromosome (in other words, half of each homologous pair), that organism is said to be haploid (represented by the symbol n).

alleles

Organisms add more cells to their bodies by

copying the cells they already have

The ploidy of the cells produced after telophase I is ________the ploidy of the original cell.

different than

During plant cell cytokinesis, a network of parallel microtubules condenses around the_________. This becomes a site of expansion of the_______, which fuses with the plasma membrane and partitions the cytoplasm into two cells.

future plane of division, cleavage furrow

Before meiosis begins, a diploid cell has two copies of each ________. During anaphase II of meiosis, _______ are separated.

homologous chromosome, sister chromatids

The likelihood of any sperm cell reaching and fertilizing any egg cell _______. This phenomenon is known as __________.

is approximately equal, random fertilization

During ________, a diploid cell undergoes genome duplication and a single division producing two ________daughter cells.

mitosis, diploid

Henrietta Lacks was female, so, naturally, all the cells from her derived cancerous cell line have chromosomes.

only X

Because of their surface-to-volume ratio, cells function most efficiently when they are relatively_____________. For organisms to grow larger, they need to add more cells.

small

Comparing these traits between both populations, it appears that the _______ has greater genetic variation within the entire population.

southern population

Special DNA sequences at the end of linear eukaryotic chromosomes are known as

telomeres

1.Creates gametes through meiosis 2.Diploid cell formed by fusion of two gamete cells; divides to form an embryo of a new organism 3.Fusion of two gamete cells 4.Mature haploid reproductive cell

1.Germ cell 2.Zygote 3.Fertilization 4.Gamete

For mice only exposed to damaged water bottles, what percentage of their oocytes developed abnormalities? Please enter your answer here:

26.9%

It appears that this HeLa cell has Your answer ______extra copies of chromosome one.

3

This HeLa cell, interestingly, has _______ copies of its sex chromosomes.

3

In a diploid organism, how much of a somatic cell's DNA came from the paternal gamete?

50 percent of the organism's total genetic material

In a mouse cell that has duplicated its DNA and is beginning mitosis, there are ___________sister chromatids.

80

Though it has been banned for use in baby bottles, BPA is still widely used to manufacture other plastic items and epoxies (such as the coating on the inside of metal cans of food). BPA-free plastics are often manufactured with a related compound, bisphenol S (BPS), which has effects similar to BPA. Imagine you are part of a group lobbying for increased control of BPA and BPS in manufactured products. How would you best summarize the results of this study to help support your case?

A 1998 study found that increasing exposure to BPA-leaching plastic sources increased the percentage of abnormalities in mouse oocytes, which could lead to an increased risk of birth defects.

Which of the following are stages in the cytokinesis of animal cells? Select all that apply.

A contractile ring of microfilaments and motor proteins forms under the plasma membrane during anaphase. The contractile ring reaches its smallest diameter, and the spindle microtubules are cut as vesicles form the new membranes that separate the two new cells. After telophase, the contractile ring constricts the plasma membrane and forms a cleavage furrow.

What occurs during the prophase stage of mitosis?

Chromosomes pack tightly and become attached to a newly forming spindle