Ch. 4 Genes and Genetic Diseases Flashcards
Which of the following bases are single-ringed structures in the DNA molecule? Cytosine and thymine Cytosine and adenine Thymine and guanine Guanine and adenine
Cytosine and Thymine
Which of the following terms best describes the DNA subunit of one deoxyribose molecule, one phosphate group, and one base? Polypeptide Double helix Nucleotide Codon
Nucleotide
Which of the following statements regarding codons is TRUE?
There are 80 possible codons.
There are 3 codons that signal the end of a gene.
There are 70 codons that specify amino acids.
Each amino acid has 1 codon.
There are 3 codons that signal the end of a gene
Which of the following describes the function of DNA polymerase? Synthesizes RNA from the DNA template Synthesizes a polypeptide Performs base pairing in replication Splits DNA molecules
Performs base pairing in replication
Which of the following best describes a silent mutation?
A change in the DNA but an amino acid change does not occur
Insertion or deletion of one or more base pairs
Increases the number or frequency of mutations
A mutation that occurs in the absence of an exposure
A change in the DNA but an amino acid change does not occur
Which of the following statements is TRUE?
Protein synthesis takes place in the cytoplasm.
DNA is replicated in the cytoplasm.
RNA is double stranded.
RNA contains the same bases as DNA.
Protein synthesis takes place in the cytoplasm
Which of the following statements is TRUE regarding base pairs? Adenine pairs with guanine. Guanine pairs with thymine. Cytosine pairs with adenine. Uracil pairs with adenine.
Uracil pairs with adenine
Which of the following terms describes the sequence for the beginning of a gene? Intron Exon Promoter site Anticodon
Promoter site
Which of the following statements regarding chromosomes is TRUE?
There are three cell types.
The somatic cells contain 46 chromosomes.
Gametes are diploid cells.
Diploid cells are formed through meiosis.
The somatic cells contain 46 chromosomes
Which of the following terms describes a cell that does not contain a multiple of 23 chromosomes? Aneuploid Monosomy Trisomy Tetraploidy
Aneuploid
Which of the following statements regarding Down syndrome is TRUE?
It occurs in 1 in 8000 live births.
Persons with Down syndrome have a normal IQ.
Persons with Down syndrome have a distinctive facial appearance.
Persons with Down syndrome are tall with good muscle tone.
Persons with Down syndrome have a distinctive facial appearance
Which of the following syndromes describes a woman born with short stature, webbing of the neck, sparse body hair, and narrowing of the aorta? Klinefelter syndrome Down syndrome Turner syndrome Fetal alcohol syndrome
Turner syndrome
A person is born with the deletion of the short arm of the chromosome 5. Which of the following syndromes will this child most likely have? Down syndrome Turner syndrome Fragile X syndrome Cri du chat syndrome
Cri du chat syndrome
.ID: 37590872 Which term best describes an allele with an observable effect? Homozygous Heterozygous Dominant Recessive
Dominant
Which of the following statements regarding autosomal dominant gene transmission is TRUE?
The affected parent transmits the gene to half of his or her children.
The affected gene is found in males only.
There is skipping of generations for transmission.
Females will transmit the disease more often than males.
The affected parent transmits the gene to half of his or her children
Which of the following is a TRUE statement regarding autosomal recessive inheritance?
Parents will always display the trait.
Approximately 50% of children will display the trait.
Males and females are affected equally.
An individual must be heterozygous to display a recessive trait.
Males and Females are affected equally
Which of the following is a TRUE statement regarding sex-linked inheritance?
Most sex-linked traits occur on the Y chromosome.
X-linked recessive diseases are more common than X-linked dominant diseases.
Females are more affected by X-linked diseases.
Females are always homozygous for X-linked traits.
X-linked recessive diseases are more common than X-linked dominant diseases
Gene products coded by the X chromosome are present in equal amounts in both males and females because:
X inactivation occurs early in embryonic development.
Males have Barr bodies that provide a second copy of the X chromosome.
Females are hemizygous.
Males have two copies of the X chromosome plus a Y chromosome.
X inactivation occurs early in embryonic development
