Chapter 10 & 11

In some parts of the United States where PBDEs are not banned, samples of human milk contain ________ PBDEs than in European countries, where this chemical is banned. 5 times less 10 to 100 times more 2 times less 2 times more 5 to 10 times more

10 to 100 times

In individuals who are the most resistant to the toxic effects of parathion, the paraoxonase enzyme is/has _________ did to genetic variations. Able to rapidly metabolism the toxic metabolite of parathion. Ten amino acid substitutions compared to the enzyme in sensitive individuals. Not found in the bloodstream. Protein folding defects. Unable to metabolize the toxic metabolite of parathion.

Able to rapidly metabolism the toxic metabolite of parathion.

Huntington disease results from extra copies of trinucleotide repeats in the Huntington gene. This is an example of a _________ mutation. Frameshift Induced Allelic expansion Nonsense Nucleotide substitution

Allelic expansion

The oxygen containing protein compounds in red blood cells that carry the iron containing heme group is?

Alpha and beta globins

Mutations that occur in somatic cells _________. Are passes into the germ cells. Are passed into the offspring. Are not passed into the offspring. Are not passed into daughter cells during cell division. Always cause cell death.

Are not passed into the offspring.

Natural sources of radiation are?

Background radiation

Chemical mutagens that incorporate into DNA or RNA molecules are called ___________. Base substitutions Tuatomeric shifts Base mimics Base analogs Mutagens

Base analogs

Mutagenic chemicals resembling nucleotides that can be incorporated into DNA or RNA during synthesis is?

Base analogs

The flaking of skin after a sunburn is an example of _______. The action of DNA repair systems Dormant cells Cancerous cells Mutations in DNA repair genes Cell suicide as a result of too much DNA damage

Cell suicide as a result of too much DNA damage

Since the urine of children with phenylketonuria contains phenylpyruvic acid, the defective enzyme in these individuals must normally _______ during the metabolism of phenylalanine. Make phenylpyruvic acid Prevent digestion of phenylalanine Convert phenylpyruvic acid to phenylalanine Convert phenylpyruvic acid to other end products. Be inactive

Convert phenylpyruvic acid to other end products.

__________ builds new DNA molecules and proofreads the new stand to detect and correct any errors. DNA repair systems RNA polymerase DNA polymerase DNA ligase RNA ligase

DNA polymerase

Lactase is an ________ that breaks down the lactose in milk into two simple molecules.

Enzyme

A stable phenotype that results from changes in the gene expression is?

Epigenetic trait

The field that deals with how gene expression is changed with permanently affecting the nucleotide sequence of DNA is?

Epigenetics

The epigenetic state of a cell is?

Epigenome

All mutations are the result of errors in a normal cellular processes such as DNA replication or are the result of natural changes in the molecular structure of the bases in DNA. True False

False

Just over 50% of the radiation that US citizens are exposed to is from background radiation. True False

False

Many of the differences people experience in response to drugs are not genetically controlled.

False

Mutation rate refers to the frequency with which mutated alleles are deleted from a genotype. True False

False

Nucleotide deletions and insertions can affect one nucleotide within a gene, or hundred to thousands of nucleotides in a gene, but does not include the duplication or deletion of the entire gene. True False

False

Pharmacogenetics is the branch of genetics that centers on developing drugs and drug treatments that are tailored to an individual's genetic makeup. True False

False

Tate preference is fully a matter of choice and is not related to any underlying genotype True False

False

The mutation that causes sickle cell anemia is due to three nucleotide substitutions in the codons of normal adult beta globins. True False

False

True or False: All individuals with cystic fibrosis have similar disease phenotypes.

False

True or False: Allelic expansion mutations always result in shortened protein products.

False

True or False: Autosomal recessive disorders are easy to identify in pedigrees because affected individuals need to inherit only one defective allele.

False

True or false: Identical twins not only have identical genotypes, but also identical phenotypes.

False

True or false: Large genes - such as the two million base-pair muscular dystrophy genes typically show a lower rate of mutation than shorter genes.

False

True or false: Mutations in somatic cells are always passed onto offspring through the egg and sperm.

False

True or false: Studies have found no correlation between the genetics of taste preferences and body weight.

False

True or false: The science of ecogenetics describes how well a pesticide or insecticide works to rid crops of pests.

False

A two-nucleotide insertion mutation that results in a conversion of an amino acid codon to a stop codon is known as a _________. Missense mutation Frameshift mutation Allelic expansion Sense mutation Nucleotide substitution

Frameshift mutation

The insertion/deletion of extra bases other than in multiples of three in DNA leading to a shift in the coding reading frame is?

Frameshift mutations

The disease _______ is caused by a disruption in the body's ability to break down galactose, one of two sugars found in lactose.

Galaxtosemia

The selective activation of silencing if either the maternal or paternal copy of a gene is called ________.

Genetic imprinting

Mutations in ________ cells are transmitted to all future generations.

Germ

Because many imprinted genes control the timing of patterns of prenatal growth, abnormal imprinting can cause ________, which is seen in disorders such as Beckwith-Weismann syndrome. Skin cancer Behavioral disorders Growth disorders DNA mutations Dwarfism

Growth behaviors

The amino acid sequence changes in any of the four proteins that make up this molecule is?

Hemoglobin variants

Why is it difficult to identify the source of an autosomal recessive mutation in a family pedigree. Heterozygous carriers can remain undetected for generations. Autosomal recessive disorder's are only observed in females. Autosomal recessive disorder's are caused by viruses. Autosomal recessive disorders are always lethal. DNA mutation rates are lower in genes that cause autosomal recessive disorders.

Heterozygous carriers can remain undetected for generations.

Methylation promoter regions in DNA send the winding of the DNA around ________, making the promoters available for transcription, hence epigenetic changes.

Histones

Measuring how DNA methylation patterns on the glucocorticoid receptor gene promoter change in response to environmental signals reveal _______. How epigenetics controls the stress response. Why identical twins have different phenotypes. The cause of depression in humans. How tightly wound the nucleosomes turn the stress response on. The cause of Beth-Weismann syndrome

How epigenetics controls the stress response.

Genetic traits that result from alterations in metabolic pathways are known as?

Inborn errors of metabolism

Individuals who are lactose intolerant do not make ________; therefore, they cannot metabolize lactose. Galactose-1-phosphate uridyl transferase Lactase Galactosemia enzymes ABO blood types Glucose-6-phosphate

Lactase

Enzymatic chains of reactions are known as?

Metabolic pathways

All bio chemical reactions through which cells convert and utilize energy is known as?

Metabolism

A process that adds a methyl group to promoter sites in DNA is?

Methylation

Mutations that result in the production of a defecting CFTR protein inserted into the cell membrane cause ________ disease phenotypes. Milder Compound No Severe Rare

Milder

A mutation in the factor VII gene - repair for blood clotting - changes a CGT codon to a CAT, and changes the amino acid from arginine to histidine. This is an example of a __________ mutation. Missense Nonsense Spontaneous Sense Frameshift

Missense

The substitution of one amino acid for another protein cause by a single nucleotide change is?

Missense mutations

Individuals who are able to taste PTC are ________. Unable to taste sugar Broccoli and Brussels sprout lovers. More sensitive to strong tastes, such as capsaicin. More obese than non tasters. Unable to taste fats

More sensitive to strong tastes, such as capsaicin.

Physical or chemical agents that cause mutations is?

Mutagens

The number of mutates alleles per gene in each generation is?

Mutation rate

Mutations that substitute one of the stop codons prematurely into the sequence if of an amino acid resulting in a shorter, unfinished protiwn.

Nonsense mutations

Mutations that alter the sequence, but not the number of nucleotides is?

Nucleotide substitutions

A new chemical compound that results from the enzyme activity on a previous compound is known as?

Product

The control region of a gene indicating the beginning of a sequence is?

Promoter

The amount of radiation that causes the same amount of damage as the standard X-ray dose is?

REM

XP is an autosomal recessive disorder caused by mutation in DNA _______ genes.

Repair

Cells that accumulate significant DNA damage may become dormant, a condition known as _________.

Senescence

Mutations that change a stop codon into one that codes for an amino acid resulting in a longer sequence and elongated proteins is?

Sense mutations

An autosomal recessive trait caused by the mutation of beta globins in the red blood cells causing them to stick together is?

Sickle cell anemia

A chemical compound acted on by an enzyme is known as a?

Substrate

True or false: Sickle cell anemia results when many genetic mutations in one individual cause production of abnormal hemoglobin molecules.

Talse

Small atomic changes within molecules that allow chemical groups, such as nucleotides, to exist in alternate geometric forms is?

Tautomeric shifts

_________ allows for non complimentary base paring, which results in permanent mutations after DNA replication. DNA polymerase X-ray radiation Nitrates Base analogs Tautomeric shifts

Tautomeric shifts

A genetic disorder caused by an imbalance in the production of alpha and beta globins is?

Thalassemia

Why are the red blood cells sickle shaped in individuals with sickle cell anemia? Genetic mutations cause fetal hemoglobin to be produced in adults. Treatment of these patients with hydroxyurea alter hemoglobin folding. The defective hemoglobin molecules form long fibers, which distort Hardin the cell membrane. Genetic mutations cause an imbalance in the production of alpha and beta globins. Several amino acid substitutions in the defective hemoglobin cause abnormal protein folding.

The defective hemoglobin molecules form long fibers, which distort Hardin the cell membrane.

______ genes tend to have high DNA mutation rates. Trinucleotide repeat-containing Short X chromosomal Dominant Autosomal

Trinucleotide repeat-containing

More than the usual number of copies in a nucleotide sequence is?

Trinucleotide repeats

Allelic expansion converts a normal allele into a mutant allele by expanding the number of trinucleotide repeats within a gene. True False

True

Certain anti-cancer drugs alter the pattern of gene expression in individuals with sickle cell animal and offer a potential new effective treatment for the disease. True False

True

During prenatal development or early in life, epigenetic responses to environmental signals can influence behavior during adulthood. True False

True

Mutated genes can produce abnormal, non-functioning, or partially functioning proteins and can also prevent the production of proteins. True Dalse

True

Mutated proteins produce changes in phenotype that range from insignificant to deadly. True False

True

New research shows that genotype should be considered as an important factor in choosing drugs and determining dosage rates for breast cancer. True False

True

Poole who find Phenylthiocarbamide (PTC) and another related compound called PROP very bitter tasting, also usually don't like kale, cabbage, broccoli, or Brussel sprouts. True False

True

Proteins are essential parts of all structures and biological processes in cells - they are the glue that holds the cells and tissues together. True False

True

Since DNA repair rates are close to the levels of DNA damage, overloading the repair systems is quite common. True False

True

Since frameshift mutations change the reading frame of the mRNA codons the wrong amino acids get inserted into the resultant protein product. True False

True

The altered hemoglobin sickle cell anemia was the first direct proof that gene mutations result in changes in the amino acid of proteins. True False

True

The size of the expanded trinucleotide repeat correlated to the earlier age of onset and the severity of the symptoms of a genetic disorder. True False

True

True or False: An individuals sensitivity to the pesticide parathion depends on his or her ability to metabolize it's toxic metabolite, paraoxon.

True

True or False: Chemicals, such as flame retardants, persist in animal and human tissue long after exposure.

True

True or False: DNA mutations can be corrected by DNA repair systems.

True

True or False: DNA mutations that lead to defective proteins may result in phenotypic changes in the individual.

True

True or False: During metabolism, enzymes catalyze the conversion of substrate molecules into products.

True

True or False: Frame shift mutations result in a change in the reading frame of mRNA codons.

True

True or False: Gene expression can be changed by chemical modifications to DNA that make promoters available for transcription.

True

True or False: Genetic variations explain differences in phenotypes, including differences in how individuals respond to certain drugs.

True

True or False: Hemoglobin defects lead to deficiencies in oxygen transport by the red blood cells.

True

True or false: Excessive DNA damage can cause cells to become cancerous.

True

True or false: Induced DNA mutations can be caused by exposure to radiation or chemicals.

True

True or false: Often, hemoglobin mutations result in amino acid substitutions in the hemoglobin protein.

True

True or false: Spontaneous mutations result from errors in DNA replication.

True

True or false: The ability of a woman to metabolize the breast cancer drug tamoxifen determines the dose that she must receive in order for the treatment to be effective.

True

True or false: The accumulation of phenylpyruvic acid in the urine of children with phenylketonuria is due to a genetic mutation that affects metabolism of the amino acid phenylalanine.

True

True or false: The maternal copy of some genes is preferentially expressed over the paternal copy; if thus pattern is not followed, growth abnormalities can result.

True

DNA methylation in promoter regions of genes _________. Occurs only before birth. Loosens the nucleosomes to allow for transcriptions. Changes the nucleotide sequence. Turns of gene expression Is irreversible

Turns of gene expression

HbA, the adult form of hemoglobin, consists of __________ and __________. Two gamma globins; two beta globins Two zeta globins; two epsilon globins Two alpha globins; two beta globins Two aloha globins; two gamma globins Four alpha globins; four gene groups

Two alpha globins; two beta globins