exam 3 genetics

missense

a nucleotide substiution that alters codon so that the encoded amino acid is substitued by a different amino acid is called a ________ mutation

the same nucleotide subsitution

in sickle cell anemia, affected individuals carry

shortened proteins

nonsense mutations produce

she was heterozygous for the disorder

Because there was no previous history of hemophilia in Queen Victoria's family, and because she transmitted the allele to only several of her children, it is reasonable to assume that

x-linked

new ______ mutations can often be detected by examining the inheritance of the trait in males

components of nucleotides

mutagenic chemicals that resemble _______ and are incorporated into DNA or RNA during synthesis are called base analogs.

replace the incorrect nucleotides that was last placed

as DNA polymerase synthesizes DNA, it can

GCT

which addition to a DNA sequence would not cause a frameshit mutation

methylation of a promotor sequence

which of the following is an example of an epigentic change?

allelic expansion

Fragile X syndrome is caused by a

all of the amino acids beyond the mutation point are changed

what occurs in a frameshift mutation?

mutagens

__________ are chemical or radiation that increase the risk of alterations of the sequence of DNA

Meiosis

a germline mutation passes to the next generation because it occurs during replication before

nonsense

a mutation that introduces a premature STOP codon would be classified as a _______ mutation

5-bromouracil … nucleotide substiution

when _______ is incorporated into DNA, it will create _________

Uracil

Deamination, the removal of an amino group, of cytosine converts it to

Xeroderma pigmentosum is due to an inablity to repair DNA.

True

Errors in DNA replication form spontaneous mutations

True

Sense mutations change a STOP codon to one that codes for an amino acid

True

DNA methylation increases transcription

False

Tautomers exhibit unconventional base pairing

true

Apoptosis, cell suicide, can be induced in cells that have excessive DNA damage

True

her affected breast cells have too many extra receptors for epidermal growth factor, and so they receive too many signals

Althea was just diagnosed with an aggressive form of breast cancer called Her-2/neu. Th cancer started because

the cells divide continously

a characteristic of all cancers is that

CML

Gleevec is a treatment for

can partially escape control of the cell cycle and lead to the formation of clusters of polyps

All epithelial cells in the inner lining of the large intestine that are heterozygous for an APC mutation

S/G2

Which is not a checkpoint within the cell cycle?

Oncogenes

Which of the following stimulates the cell cycle?

G1/S

Which checkpoint must be passed in order for DNA to undergo replication?

spread to distant parts of the body

metastasis refers to a tumor’s ablity to

cause the cell to bypass checkpoints in the cycle

cancer-causing mutations of the cell cycle

stem cells

have the property of sel-renewal by divsion

cell cycle

all cancers reflect, at the most general level, a dect in the

accumulate over a number of years

in most cases, cancer-causing mutations

monitors completion of DNA synthesis and DNA damage

during the g2/m checkpoint, the cell

tumor suppresor genes

which of the following inhibit the cell cycle

stimulation of DNA replication

if the retinoblastoma protein were mutated, which would most likely occur?

tumor suppressor

methylation of which of the following would increase the likelihood of developing cancer?

benign tumors can metastasize

false

all cancers can be diagnosed by karyotyping

false

cancer-causing mutations are always the result of chromosomal rearrangements

false

proto-oncogenes are normal functioning genes

true

oviduct

fertilization normally occurs in the

varicocele

enlarged veins in the testes, called a _________, can cause infertility

ICSI

The use of ______ is assoicated with an increased risk of transmitting genetic defects, such as as those related to infertility, onto male children

GIFT

Fertilization takes place within a woman’s body in which the following ART techniques?

PGD

What technique can be used to detect genetic defects in early stage embryos, prior to implantaion?

exon skipping within an egg

which of the following is an example of germline gene therapy?

an affected individual and all of their descendants

germline therapy would correct a genetic defect in

ex vivo

To treat severe combined immunodeficiency (SCID) by gene therapy, a patient's white blood cells are removed, and followed by the delivery of a normal gene into cells The altered cells are then returned to the patient. This is an example of which type of gene therapy?

genetic screening

an individual who is at risk of passing a genetic defect onto his or her offspring would most likely undergo

enzyme replacement therapy

the technique of ______ is a form of genetic disorder therapy in which a patient’s defective protein is artifically provided

somatic cells

nonhertiable gene therapy is performed on

prenatal testing

_________ is performed to detect genetic disorders and birth defects in a fetus

ex vivo

removing a patient’s cells, altering them by introducing a functioning copy of a gene, and the inserting them into the patient is ______ therapy

enzyme replacement therapy

Simon has Gaucher disease, in which affected individuals cannot produce glucocerebrosidase. He received recombinant glucocerebrosidase every other week in an infusion to prevent symptoms. This treatment is an example of

Gene therapy … delivery of a normal gene to affected cells in the body

_______ corrects the genetic defect in an individual with a genetic disorder by ______

retroviruses and adenoviruses

the most common vectors used in DNA therapy experiments are

low sperm motility results in the inablity of sperm to move through cervical mucus

True

azoospermia is the condition in which sperm lack flagella

false

zygote intrafallopian transfer (ZIFT) requires in vitro fertilization to be performed before embryo transfer into the oviduct

true

gene therapy has not yet cured any patient of his or her genetic disorder

false

Gene doping is an approved and widely accepted training technique for elite athletes

False

Exon skipping will often not result in a completely normal, functioning protein.

True

two

how many haplotypes does each human have>

antigen-binding site

the _______ of an antibody molecule functions to recognize and bind to a specifc antigen

lyse, due to osmosis

formation of membrane-attack complexes causes the pathogen to

antibodies

all of the following are examples of innate immunity except

dilate blood vessels, causing increased blood flow to area of infection

in an inflammatory response, the direct effect of histamine is

activated by an antigen

B and T cells become activated and divide to produce identical cells when

four

antibodies consist of _______ polypeptide chains

G

ig ______ is the most abudant antibody in plasma circulation

D

ig ______is present on many B cell surfaces

adaptive…. recognizses specific pathogens

the most effective level of defense against pathogens is the _________ immune system, because it _________

are part of innate immunity

the physical barrier of the skin and mucus produec by epitheial cells liniing body cavities

destory invading cells … guide macrophages to the infection site

the complement system functions to _____ and _______.

mast cells

_______ secrete histamine

organ rejection from recipents

the major obstacle to the use of nonhuman organs for transplant is

receptor protein are mutated and cuase an abnormal immune reponse

what is the underlying cause of Crohn’s disease

first pregnancy

which of the following is LEAST likely to be affected by Rh incompatiblity?

reverse transcriptase

HIV uses which enzyme to create DNA from an RNA template?

Because there are so many HLA allele combinations, it is rare to find unrelate individuals with same HLA haplotype

True

a person with both A and B antibodies have type O Blood.

true

A person with AB blood type produces both A and B antibodies

false

Memory B cells are short-lived cells

false

Activated B cells divide to form plasma cells and memory cells

true

The membrane-attack complex is a group of proteins that supplements the inflammatory response

true

CC-CKR5 mutations are most prevalent within African populations

False