Bio 1010 Unit 3 Exam

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Which two people would have the most different Y chromosome?

a father and his daughter's biological son

What is an "inherited" or "hereditary" cancer?

a mutation that predisposes an individual to cancer passed from parent to child

Which of the following is an example of cells undergoing mitosis?

a new embryo growing; a tree producing new branches; dead skin cells being replaced; scar tissue forming in a wound

A trait whose phenotype is determined by the interaction among alleles of more than one gene is:

a polygenic trait

You shed skin cells every day. How are these skin cells replaced?

by mitosis and differentiation of tissue stem cells

When blood cells reach the end of their lifespan, how are they replaced?

by the division of stem cells in the bone marrow

A black dog is bred with a brown dog, and all the puppies have patches of black and brown. The color coat alleles for black and brown are an example of:

codominance

If two genes are located next to one another on the same chromosome, can you use the Punnet square to assess inheritance of the two genes?

no

Which of the following mutations may be passed from parent to child?

nonlethal, lethal, and a mutation in a sperm cell

A healthy mother has no family history of cystic fibrosis. Her husband's brother has cystic fibrosis. Is the mother predicted to pass the cystic fibrosis allele to her children?

no

Mexican hairless dogs are hairless because of a dominant allele of a particular gene. Homozygous dogs die in utero (before being born). What is the probability of one hairless dog having a hairy puppy?

0

You have AB+ blood. Your spouse has AB- blood. What is the probability that your first child will have O- blood?

0

Two genes assort independently. A prospective mother is homozygous recessive for gene "A" and homozygous dominant for gene "B." The father is heterozygous for gene "A" and homozygous recessive for gene "B." What is the probability that their child will be heterozygous for both the "A" and "B" genes?

1/2

A diploid cell of baker's yeast has 32 chromosomes. How many chromosomes are in each of its haploid spores?

16

Every person has _____ alleles of the CFTR gene.

2

How many copies of any particular gene, such as BRCA1, does each person have in most of their body cells?

2

Within the general population the percentage of women diagnosed with breast cancer by age 50 is approximately _____.

2%

Mexican hairless dogs are hairless because of a dominant allele of a particular gene. Homozygous dominant dogs die in utero (before being born). What is the probability of two hairless dogs having a hairless puppy?

2/3

A human female has _____ chromosomes in each skin cell and _____ chromosomes in each egg.

46;23

A liver cell of a person with Down syndrome has _____ chromosomes.

47

A cell with 46 chromosomes enters the cell cycle. It completes all the stages EXCEPT for cytokinesis, at which point it gets "stuck." How many chromosomes will be present at this point?

92

A protein called p53 prevents a cell from entering mitosis if there are any signs of DNA damage. This type of protein is associated with:

A cell-cycle checkpoint

Cancer may be caused by:

A checkpoint problem; failure in apoptosis; unregulated cell division; failure in DNA repair mechanisms

Tumor suppressor genes produce proteins that help prevent normal cells from dividing uncontrollably by controlling cell division, apoptosis, and DNA repair. Which of the following changes in a cell might lead to cancer?

A decrease in the production of tumor suppressor protein; a lack of tumor suppressor genes

What is apoptosis?

A form of regulated cell death

In somatic cell nuclear transfer, what is transferred into what?

A somatic cell nucleus is transferred into an enucleated egg

A DNA sequence is being replicated. The nucleotide on the old strand is a "C". Which of the following could result in a mutation if inserted opposite the C on the new strand?

A, C, and T

A DNA molecule containing a gene has the sequence AACT on one strand. During replication, DNA polymerase synthesizes the sequence TTGT on the new strand. Which of the following is the most likely new allele of the original strand after replication?

AACA

Myosin is a protein expressed at high levels in muscle cells. Which of the following is true?

All cells have the myosin gene, and muscle cells express the myosin gene at high levels

Two copies of a gene have identical regulatory sequences, but different coding sequences. These copies can be referred to as _____________.

Alleles

Which of the following changes in a DNA sequence would be considered a mutation?

An extra nucleotide pair is inserted into a gene during DNA replication; A pair of nucleotides is deleted from a gene during DNA replication; Two nucleotides are deleted from a gene during DNA replication; Two nucleotides are inserted into a gene during DNA replication.

A cell has chromosomes that have two sister chromatids. What phase of the cell cycle could this cell be in?

Any stage of the cell cycle

When DNA damage is not repaired at cell cycle checkpoints, what normally occurs?

Apoptosis

DNA damage is usually repaired:

At cell cycle checkpoints

Put the following steps in order to indicate how a malignant tumor may develop. a - An environmental mutagen such as UV light mutates p53 gene. b - A single mutation of BRCA1 is inherited. c - Mutation that allows invasion of other tissues develops. d - An oncogene forms when DNA mistakes are not corrected.

B, D, A, C

You have type B blood. Therefore you can accept blood donations from people with a(n) _____ genotype.

BB and BO

Chemotherapy destroys all dividing cells. Why isn't chemotherapy typically a viable treatment option for pregnant women?

Because cells in the embryo are dividing rapidly, so chemotherapy could stop growth and development of the baby.

Why does a recipient of a liver transplant have a higher risk of bacterial infections?

Because transplant recipients have to take drugs that suppress their immune system

If a man, Bob, has one parent who smoked and died early in life from lung cancer, which of the following is most likely to be true?

Bob could inherit a mutation that leads to cancer early in life.

A male inherits a high-risk BRCA1 allele. His sister inherits the same allele. Which of the following is true?

Both siblings have a greater risk of developing breast cancer relative to males and females (respectively) without BRCA1 mutations.

Which of the following might explain why cancer cells divide uncontrollably?

Cancer cells overproduce growth signals.

If replicated chromosomes failed to condense properly as a cell entered mitosis, what would be a likely outcome?

Chromosomes would become tangled and likely break during mitosis.

Why would you need to isolate more than one type of stem cell when growing a replacement organ?

Different tissues have different stem cells; Organs are composed of more than one type of tissue

A "healthy living" or a "clean lifestyle" will guarantee that you will not develop any mutations in your DNA.

False

A mismatch that occurs during DNA replication always results in a mutation.

False

A mutation in a single allele of a tumor-suppressor gene is sufficient for a cell to become cancerous.

False

Ashkenazi Jews are the only ethnic group to carry mutations for genetic diseases.

False

Choose the list that gives the most correct and complete order of events during the cell cycle.

G1, S, G2, mitosis, and cytokinesis

_____ mutations can be passed from parent to offspring.

Germ-line

Which of the following is characteristic of scar tissue?

Humans are genetically programmed to form scar tissue at the site of a wound; It protects us from the outside world by sealing off the damaged area; Instead of forming scar tissue at the site of a wound, salamanders grow new normal tissue.

If you have a genetic predisposition to a disease such as cancer, you will eventually get cancer. Is this a true statement?

It is not necessarily true; it may be dependent on the environment

A cell has an inactivating mutation in one of its two p53 alleles. If this cell sustains DNA damage (e.g., to the HER2 gene), what is likely to happen?

It will undergo apoptosis; It will pause and repair the DNA damage before dividing.

A proto-oncogene is critical for a cell to respond to an external signal to divide. What would happen to a cell that sustains an inactivating mutation in this proto-oncogene?

It would not divide, even in the presence of a signal to divide.

Most cancerous cells have __________ mutation(s).

Many

A cell has chromosomes lined up in the center of the cell. Each sister chromatid is attached to a spindle fiber and its sister. What stage of the cell cycle is this cell in?

Metaphase

One of your good friends has a family history of breast cancer. She has her BRCA1 and BRCA2 alleles tested, and no detrimental mutations are found. She tells you she is so relieved to know that she will not develop breast cancer. Is she correct that she will not develop breast cancer?

No

Do stem cells have a larger genome than specialized cells?

No, because all cells in a person have the identical set of genes in their genome

Are all mutations harmful?

No, not all mutations change the amino acid sequence of the protein; No, some mutations are beneficial.

A cell with 46 chromosomes undergoes mitosis and cytokinesis before fully completing S phase. Which of the following would be a likely result?

None of the above

If a cell contains one chromosome with a mutated gene that increases the risk of cancer and one normal copy of the same gene, which of the following is NOT likely?

One daughter cell will receive a copy of the mutation

Why do people with inheritable high-risk mutations develop cancer at an earlier age?

People who have inherited high-risk mutations start life with at least one predisposing mutation, so they require fewer additional mutations.

In which stage(s) of mitosis would sister chromatids be connected by one centromere?

Prophase and metaphase ONLY

The diagram that is used to determine the possibilities of offspring having particular genotypes, given the genotypes of the parents, is a(n) _____.

Punnet square

A patient has a neurodegenerative disease in which brain tissue degenerates over time. In order to replace the tissue with well-matched cells, which of the following is the best option? Be sure to consider overall practicality.

Take skin cells from the patient, use them to generate induced pluripotent stem cells, and use these to treat the patient's brain

Physical side effects from chemotherapy and radiotherapy could be maximally reduced by:

Targeting specific tumor cells

A somatic mutation occurs in a 24-year-old woman. Which of the following is most likely?

The mutation will not be passed to her children.

Which of the following would you expect to differ in a comparison of normal cells versus cancer cells?

The number of DNA mutations; the proteins controlling the cell cycle; the density of cells in a tissue; the chemicals secreted by the cells

A gene encodes a protein of 350 amino acids. A mutation creates an allele that only has the first 120 amino acids. What could happen to this mutant allele?

The protein encoded by the mutant allele is shorter than the one encoded by the normal allele; The protein encoded by the mutant allele could be non-functional; The mutant allele could be associated with disease

Which of the following is NOT true of mutations?

They are changes in the protein sequence only.

Why do some people develop cancer at an earlier age than others?

They inherited at least one mutation that affects a tumor-suppressor gene.

Which of the following is true of mutations?

They may be advantageous; They may cause harm; They create new alleles in a population.

Surgery is not an effective way to treat blood cancers, such as leukemia.

True

Genghis Kahn ruled the largest empire in the world, pillaging his way across Mongolia and Asia in the thirteenth century. Today, 16 million men living in the same region are his descendants. What chromosome(s) do you think scientists examined in order to determine that these men are related to Genghis Kahn?

Y

Which of the following cell types can become the greatest number of other cell types?

a cell from an early embryo

A comparison of muscle cells and liver cells would reveal:

a different collection of proteins; the same DNA in each cell

If cells from a malignant breast tumor in a 27-year-old woman were examined, what would be expected?

a single mutation in a tumor-suppressor gene, such as BRCA1; oncogenes; a mutation that permits new blood vessel growth; a mutation in the p53 gene

Which of the following would be an example of appropriate cell division?

a skin cell dividing at the edge of a wound in response to growth signals

Into what kind of cells can totipotent stem cells develop?

any kind of cell

What are mutagens?

anything (e.g., chemicals, radiation) that can cause mutations

An organ is defined as being made up of:

at least two tissue types

Chemotherapy targets and destroys dividing cells. Skin wounds take longer than normal to heal when someone is receiving chemotherapy. Why is that?

because wound healing requires cell division

The stage in embryonic development in which the embryo is a hollow ball of cells is called a(n):

blastocyst

_____ are examples of stem cell therapy.

bone marrow transplants

From the simplest to the most complex, which is the correct hierarchy?

cells, tissues, organs, systems

The process by which a cell specializes to carry out a specific role is called:

cellular differentitation

Which of the following tissue types is/are never replaced?

cerebral cortex neurons

Side effects of chemotherapy―such as vomiting, hair loss, and bruising―occur because:

chemotherapeutic drugs kill both normal and cancerous cells.

When cancer has spread to many areas of the body, the most common form of treatment is:

chemotherapy drugs injected into the bloodstream.

You isolate cells from a tumor and study them. You observe that the cells continue dividing, even when DNA is damaged, when the cells become crowded, or even when nutrients run low. These observations lead you to suspect that the cells:

contain a mutated tumor-suppressor gene.

It has been possible for _____ to grow human skin outside the body to treat burn victims.

decades

The principle that alleles of different genes are distributed independently of one another during meiosis is:

independent assortment

"Bioprinting":

is a technique that uses computer graphics; uses "cellular ink"; can manufacture organs from scratch

_____ describes a cell with the ability to differentiate into nearly any cell type in the body.

pluripotent

___describes a cell with the ability to differentiate into nearly any cell type in the body.

pluripotent

A cloned embryo (such as a cloned mouse or sheep embryo) is genetically identical to:

the donor of the somatic cell nucleus

When amniotic fluid is tested for chromosome analysis, whose karyotype is being examined?

the embryo's

A person has a cystic fibrosis phenotype. What does this mean about the protein encoded by the cystic fibrosis gene in their cells?

the protein is not functional

Your body is actually many years younger than your chronological age.

true

A new gene is discovered, called SHOSH. It prevents a cell from entering mitosis if there are any signs of DNA damage. This means that SHOSH would be a type of _____________ and that _________ mutations in SHOSH would be associated with cancer.

tumor-suppressor gene; inactivating.

To what does gene expression refer?

turning on the expression of a gene; transcribing and translating a gene

Which of the following can cause mutations?

using tanning beds; obesity; tobacco use

An alien species has 102 chromosomes in its diploid somatic cells. Its haploid gametes will have _____ chromosomes.

51

Quitting smoking reduces a woman's risk of developing cancer by ___.

30%

A zygote has _____ chromosomes from the egg.

23

How many chromosomes are in a human sperm?

23

Approximately what percentage of women with one copy of a BRCA mutation are expected to be diagnosed with breast cancer by age 50?

30-50%

There are approximately ____ mutations in the BRCA1 gene in human populations.

600

Which of the following is the "correct" nucleotide inserted opposite an "A" during DNA replication?

T

Anemia can be the result of insufficient production of red blood cells. Which tissue is likely to be "at fault" in these cases?

Bone marrow

Worn out blood cells are produced by division of cells in the ______________.

Bone marrow

A cell cycle checkpoint should prevent the progression of a cell in which:

DNA bases are paired incorrectly

Predict what would most likely happen if both alleles BRCA1 were mutated.

DNA errors would occur more frequently.

A person with 47 total chromosomes has a karyotype that can best be described as _____.

aneuploid

A biologist measures the amount of DNA in cells growing in a laboratory. She should find that the amount of DNA doubles:

During S phase

What would be the best way to distinguish between two alleles and two genes?

Examine their DNA; the DNA sequences of two different alleles would be more similar than the sequences of two different genes.

Why would you need a gene to stop the cell cycle?

If a mutation occurred and the cell needed time to repair it before continuing; If there was no immediate need for more cells

Cells spend the majority of their time in the cell cycle in ____.

Interphase

G1 phase, S phase, and G2 phase are part of:

Interphase and the cell cycle

Why would someone with a mutation in the BRCA1 gene have a higher risk of developing cancer earlier in life than someone without a mutation in the BRCA1 gene?

It becomes more likely that additional nonhereditary mutations will occur.

What is the normal function of the BRCA1 gene?

It helps regulate the cell cycle.

Will a woman who inherits a BRCA1 mutation from her mother develop breast cancer?

She may develop breast cancer, but it depends on other factors, such as her lifetime estrogen exposure.

A 50-year-old woman who was born with a mutation in the gene encoding for a protein responsible for controlling one of the cell cycle checkpoints has developed three additional mutations in the same gene. Which of the following is likely to occur?

She will start to produce cancer cells that divide unregulated

What normally occurs when microtubules shorten during mitosis?

Sister chromatids move to opposite ends of the cell.

Why is growing a bladder more difficult than growing skin?

Skin cells are easier to grow because they grow in a sheet

Taxol interferes with the normal assembly of the mitotic spindle. How does this affect mitosis?

The cell cannot proceed normally and arrests in metaphase.

Where are sister chromatids attached to one another?

The centromere

Which of the following is NOT true for an individual with a germ-line mutation in a tumor- suppressor gene?

The individual will develop cancer at an early age.

What information would be useful in identifying the appropriate treatment for an individual's cancer?

The type of cancer; whether the cancer has metastasized; the location of cancer cells; the type of cancer and whether the cancer has metastasized

In general, what is the likelihood that women who inherit BRCA gene mutations will develop breast cancer in their lifetime compared to women without BRCA mutations?

Women who inherit BRCA mutations are more likely to develop breast cancer.

Induced pluripotent stem cells are produced from _____.

adult cells

Put the following types of stem cells in order from LEAST useful in regenerative medicine to most useful.

adult, multipotent, pluripotent, totipotent

If a nondisjunction occurs during meiosis I:

all four resulting cells will be aneuploid

In normal cells, lack of functional tumor suppressors would cause:

an accumulation of mutations in the DNA; division of damaged cells; cancer, possibly; uncontrolled cell division

Which of the following represent(s) a mutation of the sequence AGCTGCA?

an insertion of another A, immediately after the first A; removal of the second C; switching the C and the T in the middle of the sequence

A mutated form of a proto-oncogene is called:

an oncogene.

Women who inherit BRCA mutations and develop breast cancer often do so:

at an earlier age than women who do not have BRCA1 mutations.

Which of the following behaviors can help reduce the risk of developing mutations?

avoiding exposure to pesticides; not smoking; avoiding meats that have been char-grilled at high temperatures; wearing highly protective sunscreen

A person has cystic fibrosis. What does this mean about their alleles in the cystic fibrosis gene?

both are non-functional

Stem cells divide to form:

both stem cells and cells that can specialize to form tissue cells

Which of the following is placed in the correct order of increasing complexity?

cardiac cell, cardiac muscle, heart, circulatory system

A pluripotent cell that is giving signals normally given to mesenchymal cells would become:

cartilage or bone

The process by which genes are "turned on" (that is, expressed) in different cell types is termed:

differential gene expression

A zygote is _____ because it has _____ chromosomes.

diploid; 46

Male sperm are produced from _____ cells by the process of _____.

diploid; meiosis

When do homologous chromosomes separate from one another?

during meiosis 1

A woman is born with the BRCA1 breast cancer susceptibility allele. This is a "strike" against her in terms of her risk of developing breast cancer. Which of the following will reduce her risk?

eating a healthy diet, exercising, and not becoming obese

The stem cells that make up an early embryo, which can differentiate into nearly every cell type in the human body, are called:

embryonic stem cells

Which of the following is not an approach to regenerative medicine?

engineered genes

A pregnant woman has amniocentesis in order to:

examine the embryonic/fetal karyotype

A person inherits a functional cystic fibrosis allele from both parents. This person will have cystic fibrosis.

false

The products of meiosis are _____.

haploid

Relative to one of your liver cells, one of your skin cells:

has the same genome(i.e., the same genetic material); and has a different pattern on gene expression

The normal form of the BRCA1 protein is protective because BRCA1 protein:

helps cells repair damaged DNA during the cell cycle.

Investigators at a crime scene have isolated DNA from a Y chromosome and have analyzed it for STRs. They have a prime suspect, but he is not cooperating. However, several of his relatives are willing to help by donating DNA samples. Which relative will have the most similar Y chromosome?

his father's father

What is the genotype of a person with CF?

homozygous recessive

A nondisjunction occurs during meiosis II of sperm formation. Are the two homologues of the affected chromosome in aneuploid gametes identical to one another or different from one another?

identical

A pluripotent stem cell that was generated by manipulation of differentiated somatic cells is termed an:

induced pluripotent stem cell

A person has the identical BRCA1 mutation in every somatic cell in their body. What is the most likely source of this mutation?

inheritance from one of their parents (via the sperm or egg)

When chromosomes replicate during ______ phase, the end products are __________.

interphase; identical sister chromatids

Which of the following cells normally divide rapidly and are therefore affected by treatments, such as chemotherapy, that target dividing cells?

intestinal tract, hair follicle, and bone marrow cells.

Compared to an adult skin cell, an induced pluripotent stem cell:

is less differentiated; has a smaller genome

Allele A has 235 codons. Allele a (an alternative allele of the same gene) has 233 codons. When comparing the protein encoded by allele A to that encoded by allele a, protein A must be:

longer by two amino acids

The specialized type of cell division that generates genetically unique haploid gametes is:

meiosis

In meiosis, sister chromatids separate during:

meiosis ll(2)

Which of the following would most likely lead to nonhereditary cancer?

mitosis in a skin cell damaged by UV exposure

Skin color is influenced by alleles of several genes as well as exposure to sunlight. Therefore, skin color is best described as a(n) _____ trait.

multifactorial

Which of the following inheritance patterns includes an environmental contribution?

multifactorial

An interaction between genes and the environment that contributes to a phenotype or trait is:

multifactorial inheritance

Which of the following statements applies to tissues?

multiple cell types are present; each tissue has a specific function

_____ describes a cell with the ability to differentiate into a limited number of cell types in the body.

multipotent

A heart is an example of a(n) _____ that is part of the _____.

organ; cardiovascular system

In addition to breast cancer, women with a mutation in one of their BRCA genes have an increased likelihood of developing which of the following other types of cancer?

ovarian

To avoid using embryonic cells, scientists have found a way to make adult somatic cells _____ by adding genes or proteins to the cells.

pluropotent

Regenerative medicine seeks to:

prod stem cells to divide; prod stem cells to differentiate; stimulate stem cells to make cell types they wouldn't normally make

Which of the following is a normal function of tumor-suppressor genes, such as BRCA1 or p53?

produce proteins that induce apoptosis; produce proteins that repair DNA damage; produce proteins that suppress the cell cycle when there is DNA damage

The stage of meiosis in which maternal and paternal chromosomes pair and physically exchange DNA segments is called:

recombination

One of mom's chromosome 7's has a non-functional CTFR allele (cf-) next to a functional allele of another gene (A+). Her other homologue has a functional allele of the CTFR (CF+) gene next to a non-functional allele of the other gene (a-). Dad has functional alleles of both genes on both homologues (CF+, A+). A child of theirs has a maternal homologue that is CF+, A+; and a paternal homologue that is also CF+; A+. The best explanation for this is:

recombination in mom

Which of the following occurs in normal cells, but not in cancer cells?

repair of mistakes in mitosis and apoptosis in damaged cells

A mating of two people of medium height (where three genes control height): AaBbCc x AaBbCc produce _____ distinct phenotypes determined by the number of genes inherited.

seven

A woman has cystic fibrosis. Therefore:

she must have inherited a cystic fibrosis allele from both her mother and father

X-linked traits are most typically inherited by _____ from their _____.

sons; mothers

A cell that sustains an activating mutation in a tumor-suppressor gene that makes it always active would be expected to:

stop at checkpoints, even in the absence of DNA damage.

If we change a nucleotide base in the coding sequence of a gene, it may alter:

the protein's amino acid sequence; the protein's 3-D shape; the protein's folding; the protein's function.

All somatic cells in an individual contain:

the same genome

Tissues grown from a person's own cells pose no immune risk of rejection because:

the tissue is genetically related to the donor

A person's genotype refers to _____.

their genetic makeup

The visible or measurable features of an individual refer to _____.

their physical appearance

All of the following are true of adult stem cells EXCEPT:

they have the ability to differentiate into every kind of cell in the body

During meiosis, what happens to homologous chromosomes?

they move apart from one another

What is the primary mode of action of radiation therapy?

to cause extreme DNA damage

What is the normal function of a proto-oncogene?

to help the cell divide appropriately

Which of the following terms describes a cell with the ability to differentiate into any cell type in the body?

totipotent

Which of the following combinations of mutations is the most likely to convert a normal cell to a cancerous cell?

two mutated p53 alleles, two mutated BRCA1 alleles, one activated allele of HER2

How many different alleles of a gene like BRCA1 can an individual have?

two: one from their father and one from their mother

A patient has a neurodegenerative brain disease (one in which the nervous tissue of the brain is progressively lost over time). What kind of therapy might benefit this patient?

use of neural stem cells to help replace the damaged tissue, and use of drugs to stimulate division of remaining neural tissue in the brain

When do normal cells progress through the cell cycle?

when they receive a signal to divide

Mexican hairless dogs are hairless because of a dominant allele of a particular gene. Homozygous dominant dogs die in utero (before being born). What is the probability of two hairless dogs having a hairy puppy?

1/3

In a cell with a 24-hour cell cycle, approximately ___% of the time is spent in mitosis and cytokinesis.

10%

A meiotic error occurred during gamete formation resulting in an egg that has 24 chromosomes. If that egg is fertilized by a normal sperm, how many chromosomes will be in the zygote?

47

A man with straight hair marries a woman with wavy hair. What is the chance that their first child will have wavy hair?

50%

A physician is explaining treatment options to a patient who has breast cancer that has undergone metastasis. Which of the following statements might the physician use in explaining the cancer or treatment options?

Chemotherapy should be used to treat breast cancer cells circulating through the body.; Breast cancer cells that have metastasized can develop into tumors in other tissues.; Using Taxol in combination with standard chemotherapies should lead to a longer survival time than standard chemotherapy alone.; All cells undergoing mitosis will be affected by both chemotherapy and radiation.

Why does Horwitz argue that it is important for humans to protect biodiversity?

Defensive compounds produced by organisms may have medicinal uses.

A test designed to look for different alleles of a gene (e.g., the BRCA1 gene) is based on differences in:

DNA sequences

Radiation and chemotherapy can cause similar side effects although the effects are typically more localized with chemotherapy.

False

Researchers have been waging a "war on cancer" for decades. The war on cancer will be won by stopping mutations.

False

Cancer cells have multiple damaged cell cycle checkpoint mechanisms which lead to apoptosis.

False

Drugs that are hydrophobic dissolve easily in water.

False

Individuals must have an underlying genetic predisposition to develop cancer.

False

Fully differentiated stem cells can still divide.

false

In what ways would treatment of metastatic cancer differ from treatment of a malignant tumor within the liver?

Surgery would be more effective in treating the liver tumor than in treating cancer that has spread.

Which of the following is true for the younger brother of a 29-year-old woman with breast cancer?

The brother may have an increased risk for prostate cancer; The brother may not have an increased risk for cancer; The brother may develop cancer early in life; The brother may pass a mutated form of a tumor-suppressor gene onto his children.

A cell with 10 chromosomes enters the cell cycle at the G1 phase. Which of the following is true for this cell?

The cell will produce 20 sister chromatids during the S phase

Which of the following would NOT be true if a cell with 30 chromosomes did not complete S phase before mitosis?

The cell would have 60 chromosomes; The cell would have fewer organelles than a cell that completed S phase; The cell would be able to replicate chromosomes during prophase of mitosis; The cell would require more microtubules during division

What is the most likely mechanism for chemotherapy to cause diarrhea?

The cells lining the intestinal tract are mitotically active cells that divide regularly.

What will happen in a normal human skin cell if the chromosomes are not aligned for proper chromatid separation during mitosis?

The error will be noticed at a cell cycle checkpoint and the cell will not proceed unless the error is corrected.

Can apoptosis be considered protective?

Yes, it eliminates damaged cells before they can divide.

If you develop a mutation in a skin cell in a key gene involved in regulating the cell cycle, which of the following is/are possible outcomes based on that skin cell mutation?

You may develop skin cancer

A nucleotide insertion occurs in the middle of the coding sequence of a gene involved in accurately separating chromosomes during mitosis. What is/are possible outcomes?

a change in the amino acid sequence of the protein; a change in the protein's shape; a change in the protein's function; inaccurate division of the cell, resulting in cancer

A form of inheritance in which both alleles contribute equally to the phenotype is _____.

codominance

A person with type B blood makes antibodies against the "B" antigen.

false

An individual inheriting the genotype aaBbCc falls in the _____ foot phenotype.

five

The insulin gene encodes the protein hormone insulin. Insulin is critical to help maintain healthy blood sugar levels, especially after carbohydrate-rich meals. A person with a mutation in both alleles of the insulin gene may:

make nonfunctional insulin; have to watch their dietary intake of sugar; have diabetes, a condition characterized by high blood sugar; have to take insulin as a medication.

A mutation in the coding sequence of the CFTR gene does not change the amino acid sequence of the CFTR protein. This mutation is most likely to be _____.

neutral (has no effect)

A fertilized egg first gives rise to:

totipotent cells

An individual who inherits a mutation in a BRCA1 or BRCA2 gene is at higher risk for developing cancer because these genes are:

tumor-suppressor genes that produce proteins to repair DNA damage.


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