Genetic engineering has produced goats whose milk contains proteins that can be used as medicines. This effect was produced by

Mutations within a DNA sequence are

A substitution of thymine with adenine in one DNA codon causes a particular disorder. Which statement explains how the change in DNA leads to this disorder?

A rare genetic condition causes dwarfism and immunodeficiencies. Which of the following is the most likely cause of this condition?

Which of the following best describes the result of a mutation in an organism's DNA?

In phenylketonuria (PKU), an enzyme that converts one amino acid into another does not work properly. Which of the following is the most likely cause of this genetic condition?

The box below contains a statement about mutations. In many cases throughout geologic history, if mutations in the genetic material of existing species had not occurred, new species would not have appeared. Which of the following conclusions about mutations in the DNA sequence of a gene is most consistent with the statement?

A hereditary muscular disease in horses causes abnormal opening and closing of the sodium ion channels in the muscle cells. Which of the following statements describes the most likely origin of this disease?

Huntington’s disease (HD) is a hereditary disease that destroys brain cells. In individuals with HD, the functioning of a specific protein is altered, and this leads to the disease’s effects. Which of the following is the most likely cause of the altered protein function in individuals with HD?

During DNA replication, the wrong nucleotide was inserted in the DNA sequence. Which of the following terms describes this situation?

Crossing-over most commonly results in

What technology was made possible by the discovery of the structure of DNA?

Scientists have altered crop plants to make them more resistant to insects and disease. Which of these processes makes it possible for scientists to alter plants?

Which of these is an environmental factor that causes damage to chromosomes?

Which of these describes a mutation that can be inherited?

Which of these results when one nitrogen base replaces another in a segment of genetic material?

A rare disorder is caused by changes in a gene. Parents of individuals with the disorder have only normal copies of this gene. Which of these most likely causes this disorder?

Certain plant crops are genetically engineered to grow faster and resist disease. These genetically engineered plant crops cannot reproduce because they have a “terminator” gene that keeps their seeds from sprouting. However, once the genetically engineered plant crops are planted outside, they may cross-pollinate with unaltered plant crops. The use of terminator genes is least likely to result in

In the laboratory, scientists remove the gene for insulin from human chromosomes. They insert the gene into the DNA of bacteria. This causes the bacteria to produce human insulin. The insulin is used to treat diabetes in humans. Which of these describes this process?

Two segments of DNA are shown in the diagram below. Normal thymine (T) is found in the old strand. It is replaced by an abnormal molecule (T*) in the new strand. The abnormal molecule (T*) binds to guanine (G) instead of binding to adenine (A). This is an example of

Most bacteria do not have the ability to break down oil that is accidentally spilled into the ocean by tankers. However, scientists can insert a gene into the DNA of a bacterium to give it the ability to break down the oil. This technology is an example of

When the segment of human DNA that codes for insulin production is inserted into bacterial DNA, the bacterium begins producing human insulin. Which of these best identifies the process by which human DNA is inserted into bacterial DNA?

Scientists can genetically alter corn so that it makes a protein that will harm a certain caterpillar that feeds on it. Which of the following is an advantage of producing this type of corn?

Risks of having genetic mutations are increased with excessive exposure to—

Red blood cells contain the protein hemoglobin which aids in transportation of the respiratory gases. Most humans have a form of hemoglobin called hemoglobin A. Individuals with sickle cell anemia have a very similar form called hemoglobin S. This hemoglobin is slightly changed in shape and has a reduced ability to transport oxygen. It is the presence of hemoglobin S that results in the signs and symptoms of sickle cell anemia. Which of the following is the expected cause of the production of hemoglobin S?

A botanist inserts a new gene sequence into a pink-flowering plant. He hopes that the genetically modified plant will now produce blue flowers. In nature, which of the following processes would result in this kind of change?

Which of the following chromosome pairs contain the above chromosomes after crossing over is complete?

The table shows a mutation in a DNA sequence. Original Sequence: GCA TAGT GCT ATA GCG ACT Mutated Sequence: GCA TTC CTA TAG CGA CT What is the result of this mutation during the translation process?

Which genetic abnormality can be identified through karyotyping?

Which would best allow a species to survive environmental changes?

Which would most likely produce a mutation that is passed on to offspring?

Which will most likely cause variations to occur within a species?

Instead of using chemicals to destroy some insects, scientists are now able to produce a type of corn that will repel insects. How are scientists able to produce this type of corn?

Which will most likely cause a gene to mutate?

A mutation occurs in the genes that code for coat color in deer. Which change will most likely result from this mutation?

This chart shows a list of messenger RNA codons. A strand of DNA with the sequence AAC AAG CCC undergoes a mutation, and the first A is changed to a C. How will this mutation affect the amino acid sequence?

Which of these would most likely cause a mutation?

One human disease is caused by a change in one codon in a gene from GAA to GUA. This disease is the result of

This segment of DNA has undergone a mutation in which three nucleotides have been deleted. A repair enzyme would replace them with

Radon is a radioactive gas that is sometimes present in homes. If radon is inhaled, its decay products are deposited in the lungs. Radioactive particles can penetrate cells and cause changes to the cells' DNA. These changes in DNA are an example of which of the following?

People who inherit hemophilia type A are unable to make a protein required to clot blood. This disorder is directly related to which of the following?

What is the mode of inheritance shown in the pedigree?

The pedigree below shows the transmission of a disorder within a family. Which statement describes the offspring that would result if individual 1 has children with a woman that does not carry the allele for this disorder?

One of the dogs has progressive retinal atrophy, a condition that damages the retina. What are the genotypes of dog 1 and dog 2?

What is the genotype of individual 6?

How would overexposure to X-rays affect most animal cells?

A genetic mutation resulted in a change in the sequence of amino acids of a protein, but the function of the protein was not changed. Which statement best describes the genetic mutation?

Which stage in the diagram shows the separation of the original DNA molecule into two complementary strands?

Fill in the blank: The letters __, __, __, and __ represent the four nucleotides in DNA.

After DNA replication, the result is two complete DNA molecules.

A partial DNA sequence for normal hemoglobin and a partial DNA sequence for sickle-cell anemia are shown below. G-G-A-C-T-T-C-T-T Normal hemoglobin G-G-A-C-A-T-C-T-T Sickle-cell anemia Based on the DNA sequences, sickle-cell anemia is caused by

The chromosome numbered 1 through 22 are known as

The preparation of these charts for individuals A and B is known as

Which genetic disorder in individual A is indicated by the number of chromosomes labeled 21?

A change in the sequence of nitrogenous bases in DNA may result in

A change that alters the base sequence in an organism's DNA is called a

Down syndrome is a genetic disorder caused by the presence of an extra chromosome number 21 in the body cells of humans. This extra chromosome most likely is a result of

Select the technique, chosen from the list below, that is best described by the statement shown. This technique involves the use of a photograph to study the homologous pairs of chromosomes of an individual in order to detect genetic disorders.

Certain genetic disorders can be detected by preparing and studying an enlarged photograph of paired chromosomes from a cell. The preparation of this photograph is known as

The diagram shown represents a photographic enlargement of replicated chromosomes from a fetal cell. For which technique would this photograph be used to determine if the chromosomes of the fetus exhibit any genetic abnormalities?

Down syndrome in humans may result from

X rays, formaldehyde and asbestos fibers are all similar in that they are

The preparation of an enlarged photograph showing paired homologous chromosomes is known as

An analysis of chromosomes may show the loss of a portion of a chromosome. This type of chromosomal change is known as

The use of chemicals such as formaldehyde and asbestos has decreased because they have been

Select the term, chosen from the list below, that is best described by the statement shown. A photograph of paired human chromosomes is prepared.

Which genetic disorder is usually detected by analyzing a karyotype?

Select the genetic technique, chosen from the list below, that is best described by the statement shown. Enlarged photographs of homologous chromosomes are prepared for examination to detect chromosomal defects.

The diagram represents a

The chromosomes are arranged to show

The individual from whom these chromosomes were taken is a

This chromosomal arrangement indicates that the individual has

Substances that increase the chance of gene alterations are known as

In humans, Down syndrome is often a result of the

Which phrase best describes a human with the chromosomes represented in the diagram shown?

The technique known as karyotyping is used to detect abnormalities in

The addition, removal, or substitution of nitrogenous bases in a DNA molecule may be caused by

Mutations can be transmitted to the next generation only if they are present in

A karyotype is shown in the diagram. Information in this karyotype indicates that the individual is a

Genetic information is shown in the diagram. This type of diagram is used to

The arrangement of chromosomes shown in the diagram is known as

Examination of the diagram indicates that these are the chromosomes of a

The genetic disorder shown in the diagram most likely resulted from

Which technique was used to organize the chromosomes as shown in the diagram?

For each phrase in the following question(s), select the genetic disorder that is most closely associated with that phrase. Changes in speech patterns and mental retardation due to the presence of an extra chromosome

A single change in the sequence of nitrogenous bases in a DNA molecule would most likely result in

The chromosomes of a person with a genetic disorder are shown in the diagram below. This genetic disorder resulted from