Week 6 Mastering Biology

Humans are diploid and have 46 chromosomes (or two sets). How many sets of chromosomes are found in each human gamete?

1

Which syndrome is characterized by the XO chromosome abnormality?

Turner syndrome

Sex-Linked Pedigrees Part D

X B X b

A male knows for sure he does not have hemophilia, what genotype must he be?

X H Y 0

Which of these is NOT a carcinogen? UV light testosterone cigarette smoke fat all of the above are carcinogens

all of the above are carcinogens

Centromeres divide and sister chromatids become full-fledged chromosomes during _____.

anaphase

Homologous chromosomes migrate to opposite poles during _____.

anaphase I

During _____ sister chromatids separate.

anaphase II

Mutant tetraploid plants _____.

are unable to interbreed with a diploid plant

Since 1991, deaths from breast and colorectal cancer in the United States are down 35%. What is the main reason for this?

better screening

Homologous pairs of chromosomes are lined up independently of other such pairs during _____.

metaphase I

During _____ chromosomes align single file along the equator of a haploid cell.

metaphase II

Crossing over, resulting in an increase in genetic variation, occurs between _____.

nonsister chromatids of homologous chromosomes

Which of these terms applies to an organism with extra sets of chromosomes?

polyploid

Which of the following organisms would be most similar to humans in a study that involved the response of cancer cells to various medications?

primates

Spindle fibers attach to kinetochores during _____.

prometaphase

Chromosomes become visible during _____.

prophase

Synapsis occurs during _____.

prophase I

During _____ a spindle forms in a haploid cell.

prophase II

Cytokinesis often, but not always, accompanies _____.

telophase

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids.

telophase I

At the end of _____ and cytokinesis there are four haploid cells.

telophase II

_____ is the process by which haploid gametes form a diploid zygote.

Fertilization

Human gametes are produced by _____.

meiosis

If a mother is bald and the father is normal what are the odds of her son being bald

100%

A diploid organism whose somatic (nonsex) cells each contain 32 chromosomes produces gametes containing _____ chromosomes.

16

When did the United States declare a "war on cancer" by passing the National Cancer Act?

1971

In human gamete production there is an average of _____ crossover events per chromosome pair.

2-3

Humans are diploid and have 46 chromosomes. How many chromosomes are found in each human gamete?

23

Normal human gametes carry _____ chromosomes.

23

A particular diploid plant species has 48 chromosomes, or two sets. A mutation occurs and gametes with 48 chromosomes are produced. If self-fertilization occurs, the zygote will have _____ set(s) of chromosomes.

4

Which of the following is closest to the current average annual death rate from cancer in the United States?

580 thousand

If a diploid cell undergoes meiosis and produces two gametes with n + 1 chromosomes and two gametes with n− 1 chromosomes, what type of error occurred?

A nondisjunction error occurred in meiosis I, in which both members of a homologous pair migrated to the same pole of the cell.

If a diploid cell undergoes meiosis and produces two gametes that are normal, and one with n − 1 chromosomes, and one with n + 1 chromosomes, what type of error occurred?

A nondisjunction error occurred in meiosis II, in which both sister chromatids of a chromosome migrated to the same pole of the cell.

What kind of cell results when a diploid and a haploid gamete fuse during fertilization?

A triploid cell

When can nondisjunction occur? Choose the best answer. In meiosis, when homologous chromosomes fail to separate In meiosis, when sister chromatids fail to separate In mitosis, when sister chromatids fail to separate All three answers are correct.

All three answers are correct.

What is a nondisjunction?

An error in cell division that causes homologous chromosomes or sister chromatids to move to the same side of the dividing cell

Which of these gametes contains one or more recombinant chromosomes?

B and C

Which of these gametes contain one or more recombinant chromosomes?

B, C, F, and G

Which of these cells is (are) haploid?

C and D

Which of these phases includes all of the stages of mitosis but no other events?

E

Which of the following best describes the advantages of the personalized care technique described in the video?

Fruit flies make excellent models because we can create a strain of flies with a specific type of tumor, then raise thousands of flies in order to test the effects of medications.

Of the following chromosomal abnormalities, which type is most likely to be viable in humans?

Trisomy

Based on the information in the video, which of the following correctly answers these three questions: What was the leading cause of death in the United States in the early 1970s? What is the leading cause of death in the United States today? What is predicted to be the leading cause of death in the United States 10 years from now?

cancer; cardiovascular disease; cancer

Which processes lead to most genetic variation in sexually reproducing organisms? Select all that apply.

crossing over independent assortment of chromosomes in meiosis random fertilization

_____ is a carcinogen that promotes colon cancer.

fat

Meiosis II typically produces _____ cells, each of which is _____.

four ... haploid

Most polyploid plants arise as a result of _____.

hybridization

During _____ the cell grows and replicates both its organelles and its chromosomes.

interphase

Nucleoli are present during _____.

interphase

Sex-Linked Pedigrees Part E

it could be X B X B or X B X b

Why is the "personalized care" plan described in the video, in which treatments are tailored for each individual, much more promising than previous treatment plans?

the genetic mutations that cause cancer vary from patient to patient

During _____ both the contents of the nucleus and the cytoplasm are divided.

the mitotic phase

Meiosis I produces _____ cells, each of which is _____.

two ... haploid