Biology Unit 4 quiz

Which type of mutation will usually have the most detrimental effect on organisms function and why?

A deletion because there will be no protein product produced for genes in the affected region

DNA is used as a template to make a complementary strand of DNA.

DNA replication

Consider a normal chromosome with the following gene sequence along its length: F G H I J K L. Which of the following sequences represents an inversion?

FGKJIHL

All codons code for amino acids.

False

Most codons code for more than one amino acid.

False

Only 20 different codons are used to code for amino acids.

False

Why might a gene duplication mutation be a positive evolutionary force?

If there are two genes one is free to mutate and take on a different function

What is a difference between DNA replication and RNA transcription

In DNA replication the helix is never closed after it is opened by helicase, but once RNA polymerase has finished transcribing a region the double helix closes.

Why is RNA synthesis called 'transcription' and protein synthesis called 'translation?'

RNA synthesis makes a complementary copy of the DNA using nucleic acid and protein synthesis requires the information in the RNA to be changed into a different type of molecule

The following sequences of DNA is the normal, wild type gene. 5'TAC CGG TTA GTT AGC CGA TAG 3' an insertion occurs during DNA replication, causing an additional adenine to be inserted into the nucleotide strand after the guanine shown in red. What effect will this have on the final protein?

The addition of the A will cause a frameshift, resulting in a premature stop codon and a truncated protein.

A single point mutation has occurred a gene causing a stop codon to appear early in the translation of the protein. What effect will this have on the protein?

The early stop codon will cause termination to occur earlier, and the protein will be abnormally short.

A mutation occurred in the third codon position of a gene, but the protein still functions normally. How is this possible?

The genetic code is redundant, so that mutations in the third position of the codon often result in the same amino acid being specified.

A nucleotide deletion in DNA replication

causes the amino acids inserted after the deletion to be incorrect

A mutation that causes a change in a single nucleotide in DNA

changes the corresponding nucleotide in mRNA, resulting in a different codon.

When a chromosome is broken in two places and reconnected so that a region is flipped from the normal order, this is called

inversion

RNA is used as a template to make a complementary strand of RNA

none of these

RNA is used as a template to make a complementary strand of DNA.

reverse transcription

Which of the following occurs when a piece of one chromosome breaks off and is attached to another chromosome?

simple translocation

DNA is used as a template to make a complementary strand of RNA

transcription

A lack of amino acid availability would affect what stage in gene expression?

translation

RNA is used as a template to make a polypeptide.

translation

At what point in gene expression do molecules go from being information storage molecules to metabolic and structurally functional molecules?

when RNA is translated into protein

An organism possesses an inversion in only one homologue of a chromosomal pair. When this organisms germ cells undergo meiosis, how many of its gametes will also possess the inversion

1/2if it's gametes

In some cases it is possible to change the sequence of bases in a codon and it will still code for the same amino acid

True

Most amino acids are specified by more than one codon

True

The start codon has a dual function because it also codes for an amino acid

True