Chapter 19

Missense

A base substitution in DNA that ultimately leads to a change in the encoded amino acid is called a(n) mutation.

where the two sister chromatids of a replicated chromosome are joined where two chromosome pieces break and rejoin with other chromosome pieces of the cell cycle where chromosomes are more susceptible to breaking

A breakpoint refers to the region ______.

Substitution

A change of one base for another is described as a base __________ mutation.

silent

A mutation that does not change the amino acid sequence of a polypeptide is known as a(n) ____________ mutation.

nonsense

A mutation that results in a premature termination of the synthesis of a polypeptide is called a(n) mutation.

change to the amino acid sequence of the polypeptide

A silent mutation is a mutation that results in no ______.

temporary change in base structure

A tautomeric shift is a ______.

tautomeric shifts

A temporary change in base structure due to movement of hydrogen atoms is called a(n) .

Tautomers

Bases which exist in keto and enol or amino and imino forms are best described as ______.

germ cells

Cells that give rise to the gametes such as eggs and sperm are called _______ ________

oxidative DNA damage

Changes to DNA structure caused by reactive oxygen species (ROS) are termed __________ ___________ __________

wild-type

In a natural population, a _____-_____ genotype is the most common one.

Intergenic suppression

In this figure, two panels are shown. Panel I shows protein A. A first mutation inhibits the function of protein A. In Panel II a second mutation alters protein B to carry out the function of protein A. What is this an example of?

reactive oxygen species

Oxidative DNA damage refers to changes in DNA structure that are caused by ______.

both X-rays and UV light

Physical mutagens include ______.

bacterial colonies are transferred from one plate to another with a sterile piece of velvet cloth

Replica plating is a technique in which ______.

apurinic site

The red arrow in this figure points to a(n) .

breakpoint

The region where two chromosome pieces break and re-attach to other chromosome pieces is called a chromosomal ________ .

Depurination

The removal of a purine from DNA is called

Deamination

The removal of an amino group from a base is called

cells that produce sperm and eggs

The term germ line is used to describe the ______.

mutation

The term refers to an inherited change in the sequence of the genetic material.

are bases, which exist in keto and enol forms or amino and imino forms.

Which of the following are forms of tautomers?

Up promoter mutations cause the promoter sequence to be more like the consensus sequence Down promoter mutations decrease the affinity of transcription factors to the promoter

Which of the following statements about promoter mutations is true?

Mutation

A heritable change in the genetic material is called a(n) ______.

has a different DNA sequence from the wild type.

A mutant allele is best defined as an allele that ______.

In this figure, two panels are shown. Panel I shows protein A. A first mutation inhibits the function of protein A. In Panel II a second mutation alters protein B to carry out the function of protein A. What is this an example of?

Intergenic suppression

spontaneous, induced

Mutations can be caused in two main ways: (1) _____ mutations are the result of natural biological or chemical processes; and (2) ______ mutations are produced by environmental agents.

UP ; DOWN

Mutations that occur in a promoter sequence can be divided into two types: ______________ promoter mutations increase the transcription rate, while _____________ promoter mutations decrease it.

depurinations

Mutations that remove an adenine or guanine from the DNA are known as ______.

apurinic

The covalent bond between deoxyribose and a purine base is rather unstable and can undergo a spontaneous reaction with water. The breaking of the bond releases the base, and leaves a(n) site in the DNA.

increase generation after generation

Trinucleotide repeat expansions are repeated sequences of three nucleotide bases which ______.

mutant

An allele that has a DNA sequence different from that of the wild-type is called a(n) allele.

base substitution

This figure best illustrates what type of mutation?

spontaneous, induced.

Errors in DNA replication are examples of ______ mutations, while mutations caused by ultraviolet light are ______ mutations.

typically

The wild type genotype or phenotype is the one that is ______ found in nature.

Deamination

This figure highlights the process of ______.

Blank 1: replica Blank 2: plating

This figure shows a technique known as _____ _____

Uracil,hypoxanthine

The mutagen nitrous acid changes cytosine to ____ and _____ adenine to .

Missense

A mutation in a gene that causes an amino acid change in the encoded protein is called a ______ mutation.

intragenic suppressor

This figure shows an example of a(n) _______ __________ mutation.

Mutagens

An agent that can change DNA structure and cause mutations is known as a(n) .

Base substitution

This figure best illustrates what type of mutation?

Nonsense mutations

What type of mutations involve a change from a normal codon to a stop codon?