Free BACE Genetics Questions and Answers 2

Question 1

What is the central dogma of molecular biology?

Accepted Answer

DNA to RNA to Protein describes the flow of genetic information from storage to functional form

Answer

Protein to RNA to DNA describes how proteins direct their own synthesis

Answer

RNA to DNA to Protein describes retroviral replication

Answer

Protein to DNA to RNA describes the reverse process in eukaryotes

Question 2

What is the difference between a gene and an allele?

Accepted Answer

A gene is a hereditary unit encoding a trait; an allele is one of the alternative forms of that gene at a specific chromosomal locus

Answer

A gene is a segment of DNA; an allele is a segment of RNA

Answer

A gene is found in somatic cells; an allele is found only in germ cells

Answer

A gene exists only in diploid organisms; an allele exists in haploid organisms

Question 3

What is the result of a frameshift mutation in a protein-coding gene?

Accepted Answer

A shift in the reading frame that alters all downstream codons usually producing a truncated or non-functional protein

Answer

A single amino acid change in the resulting protein at the site of the mutation

Answer

Complete loss of gene function due to failure to transcribe the mutated DNA

Answer

Increased protein production due to creation of an alternative start codon

Question 4

What is a promoter in the context of gene expression?

Accepted Answer

A DNA sequence upstream of a gene where RNA polymerase binds to initiate transcription

Answer

A protein that promotes translation by binding ribosomes to mRNA

Answer

An RNA sequence that promotes efficient ribosome binding for translation

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A protein that promotes DNA methylation to silence gene expression

Question 5

What is the purpose of gel electrophoresis in genetic analysis?

Accepted Answer

To separate DNA fragments by size in an electric field for visualization and analysis

Answer

To amplify specific DNA sequences from small amounts of starting material

Answer

To sequence DNA by determining the exact nucleotide order of fragments

Answer

To cut DNA at specific recognition sequences using restriction enzymes

Question 6

What is epigenetics in the context of gene regulation?

Accepted Answer

Heritable changes in gene expression that do not involve changes in the DNA nucleotide sequence (e.g., methylation, histone modification)

Answer

Mutations in the DNA sequence of genes that are inherited by daughter cells

Answer

The process by which genes are transcribed faster in response to environmental signals

Answer

The study of genetic differences between species in their promoter sequences