Question 1

The dominant oncogene, ras

Accepted Answer

A)  stimulates rates of mitosis when activated in a normal cell. 
B)  can be expressed constitutively when mutated. 
C)  is the gene for a protein which is part of a signal transduction pathway. 
D)  All of the answers are correct. 
E)  None of the answers are correct. 
A)  stimulates rates of mitosis when activated in a normal cell. 
B)  can be expressed constitutively when mutated. 
C)  is the gene for a protein which is part of a signal transduction pathway. 
D)  All of the answers are correct. 
E)  None of the answers are correct.

Question 2

A tumorous cell is not a cancer because

Accepted Answer

A)  it has not lost the ability to undergo apoptosis. 
B)  tumorous cells are localised, whereas cancer cells can metastasise. 
C)  it may still be able to repair any DNA mutations. 
D)  it is not necessarily caused by a genetic change. 
E)  tumorous cells are undifferentiated. 
A)  it has not lost the ability to undergo apoptosis. 
B)  tumorous cells are localised, whereas cancer cells can metastasise. 
C)  it may still be able to repair any DNA mutations. 
D)  it is not necessarily caused by a genetic change. 
E)  tumorous cells are undifferentiated.

Question 3

Barley has a genome of 5.3 Gb. This is the same as

Accepted Answer

A)  53 000 000 000 000 bp. 
B)  53 billion base pairs. 
C)  530 billion base pairs. 
D)  530 000 000 bp. 
E)  5300 Mb. 
A)  53 000 000 000 000 bp. 
B)  53 billion base pairs. 
C)  530 billion base pairs. 
D)  530 000 000 bp. 
E)  5300 Mb.

Question 4

Excision repair only works because

Accepted Answer

A)  it removes entire sections of damaged double-stranded DNA and replaces them. 
B)  the excised single strand is accurately reformed from its complementary strand. 
C)  the excision repair enzymes recognise DNA damage and remove the double-stranded DNA in the area. 
D)  most DNA sequences are non-coding. 
E)  it occurs after DNA replication. 
A)  it removes entire sections of damaged double-stranded DNA and replaces them. 
B)  the excised single strand is accurately reformed from its complementary strand. 
C)  the excision repair enzymes recognise DNA damage and remove the double-stranded DNA in the area. 
D)  most DNA sequences are non-coding. 
E)  it occurs after DNA replication.

Question 5

Spontaneous mutations

Accepted Answer

A)  are rare, because of the semiconservative nature of DNA synthesis. 
B)  occur most frequently as a result of deamination (loss of cytosine or thymine). 
C)  cannot be repaired. 
D)  are due to translocation of one region of the chromosome to another region in the DNA. 
E)  occur at a rate of approximately one in one billion. 
A)  are rare, because of the semiconservative nature of DNA synthesis. 
B)  occur most frequently as a result of deamination (loss of cytosine or thymine). 
C)  cannot be repaired. 
D)  are due to translocation of one region of the chromosome to another region in the DNA. 
E)  occur at a rate of approximately one in one billion.

Question 6

The genome of a virus is composed of

Accepted Answer

A)  double-stranded DNA. 
B)  single-stranded DNA. 
C)  double-stranded RNA. 
D)  single-stranded RNA. 
E)  Any of these types of DNA or RNA. 
A)  double-stranded DNA. 
B)  single-stranded DNA. 
C)  double-stranded RNA. 
D)  single-stranded RNA. 
E)  Any of these types of DNA or RNA.

Question 7

Variation between individuals of a species

Accepted Answer

A)  is solely a result of genetic differences. 
B)  has its primary source in environmental effects. 
C)  is a result of the deletion of specific genes. 
D)  is the basis upon which natural selection acts. 
E)  is greater than variation between members of different species. 
A)  is solely a result of genetic differences. 
B)  has its primary source in environmental effects. 
C)  is a result of the deletion of specific genes. 
D)  is the basis upon which natural selection acts. 
E)  is greater than variation between members of different species.

Question 8

Transposons are

Accepted Answer

A)  DNA sequences that are able to replicate and insert into another location in the genome. 
B)  maintained in the genome as they are replicated during genomic DNA replication. 
C)  genes which frequently encode enzymes which are able to recognise specific sequences to DNA and cut them. 
D)  able to produce RNA copies of themselves. 
E)  All of the statements are correct. 
A)  DNA sequences that are able to replicate and insert into another location in the genome. 
B)  maintained in the genome as they are replicated during genomic DNA replication. 
C)  genes which frequently encode enzymes which are able to recognise specific sequences to DNA and cut them. 
D)  able to produce RNA copies of themselves. 
E)  All of the statements are correct.

Question 9

Organelle genomes

Accepted Answer

A)  are composed of linear DNA. 
B)  are composed of circular DNA. 
C)  may be linear or circular DNA. 
D)  contain all the genes necessary for the functioning of the genome. 
E)  are all very small. 
A)  are composed of linear DNA. 
B)  are composed of circular DNA. 
C)  may be linear or circular DNA. 
D)  contain all the genes necessary for the functioning of the genome. 
E)  are all very small.

Question 10

To manufacture DNA, the cell needs a balance in the levels of purine and pyrimidine nucleotides. This balance is controlled by

Accepted Answer

A)  the enzyme ribonucleotide reductase. 
B)  feedback mechanisms. 
C)  the level of ATP in the cell. 
D)  restriction enzymes. 
E)  pinocytosis of precursors. 
A)  the enzyme ribonucleotide reductase. 
B)  feedback mechanisms. 
C)  the level of ATP in the cell. 
D)  restriction enzymes. 
E)  pinocytosis of precursors.

Question 11

Which of the following statements about chloroplast chromosomes is CORRECT?

Accepted Answer

A)  Chloroplasts contain multiple copies of circular DNA. 
B)  Chloroplasts contain a single, circular DNA molecule. 
C)  Chloroplasts contain a single, circular RNA molecule. 
D)  Chloroplast chromosomes are replicated in the nucleus of the cell. 
E)  Chloroplasts do not contain chromosomes. 
A)  Chloroplasts contain multiple copies of circular DNA. 
B)  Chloroplasts contain a single, circular DNA molecule. 
C)  Chloroplasts contain a single, circular RNA molecule. 
D)  Chloroplast chromosomes are replicated in the nucleus of the cell. 
E)  Chloroplasts do not contain chromosomes.

Question 12

Which of the following statements about DNA is CORRECT?

Accepted Answer

A)  Only 2 per cent of mammalian DNA codes for polypeptides. 
B)  Transposable elements repair DNA damage. 
C)  Introns are segments of genes that are inserted at replication forks. 
D)  DNA synthesis is self-perpetuating and does not require enzyme mediation. 
E)  Mitochondrial DNA is replicated in the nucleus. 
A)  Only 2 per cent of mammalian DNA codes for polypeptides. 
B)  Transposable elements repair DNA damage. 
C)  Introns are segments of genes that are inserted at replication forks. 
D)  DNA synthesis is self-perpetuating and does not require enzyme mediation. 
E)  Mitochondrial DNA is replicated in the nucleus.

Question 13

Non-coding DNA can best be described as

Accepted Answer

A)  'junk' DNA that is of little or no value to the organism. 
B)  including stretches of DNA that may have an as yet undefined function for the organism. 
C)  DNA that is the promoter region for genes. 
D)  DNA that is composed of repetitive sequences of bases. 
E)  DNA that codes for factors that regulate gene expression. 
A)  'junk' DNA that is of little or no value to the organism. 
B)  including stretches of DNA that may have an as yet undefined function for the organism. 
C)  DNA that is the promoter region for genes. 
D)  DNA that is composed of repetitive sequences of bases. 
E)  DNA that codes for factors that regulate gene expression.

Question 14

Humans have

Accepted Answer

A)  forty-four autosomes and two sex chromosomes. 
B)  twenty-two autosomes and two sex chromosomes. 
C)  twenty-four autosomes and two sex chromosomes. 
D)  twenty-two autosomes, including two sex chromosomes. 
E)  twenty-four autosomes, including two sex chromosomes. 
A)  forty-four autosomes and two sex chromosomes. 
B)  twenty-two autosomes and two sex chromosomes. 
C)  twenty-four autosomes and two sex chromosomes. 
D)  twenty-two autosomes, including two sex chromosomes. 
E)  twenty-four autosomes, including two sex chromosomes.

Question 15

A tumour suppression gene is

Accepted Answer

A)  a gene whose normal function is gained during the development of cancer. 
B)  a dominant gene that plays a role in cell proliferation. 
C)  the gene Rb that suppresses cell progression to M phase during cell division. 
D)  a gene frequently associated with DNA transcription enzymes. 
E)  a gene when mutated is associated with an inherited susceptibility to cancer. 
A)  a gene whose normal function is gained during the development of cancer. 
B)  a dominant gene that plays a role in cell proliferation. 
C)  the gene Rb that suppresses cell progression to M phase during cell division. 
D)  a gene frequently associated with DNA transcription enzymes. 
E)  a gene when mutated is associated with an inherited susceptibility to cancer.

Question 16

Which of the following statements is CORRECT?

Accepted Answer

A)  Cancer is caused by genetic alterations to cells. 
B)  The majority of cancers are sporadic (i.e. there is no family history). 
C)  Tumours are clonal in origin. 
D)  Cancer is not an inherited disease, but the predisposition to cancer is genetic. 
E)  All of the answers are correct. 
A)  Cancer is caused by genetic alterations to cells. 
B)  The majority of cancers are sporadic (i.e. there is no family history). 
C)  Tumours are clonal in origin. 
D)  Cancer is not an inherited disease, but the predisposition to cancer is genetic. 
E)  All of the answers are correct.

Question 17

Which of the following statements is true?

Accepted Answer

A)  Somatic cells of organisms can be diploid, tetraploid or even hexaploid. 
B)  Eukaryotic genomes sometimes include plasmids. 
C)  Eukaryotic genomes are completely composed of linear DNA. 
D)  All of the above are correct. 
E)  Eukaryotic genomes include all of the DNA within the cell. 
A)  Somatic cells of organisms can be diploid, tetraploid or even hexaploid. 
B)  Eukaryotic genomes sometimes include plasmids. 
C)  Eukaryotic genomes are completely composed of linear DNA. 
D)  All of the above are correct. 
E)  Eukaryotic genomes include all of the DNA within the cell.

Question 18

Given that different organisms can have sections of DNA that are almost identical, which of the following statements is CORRECT?

Accepted Answer

A)  This DNA is usually non-functional. 
B)  This constitutes evidence of evolution of these organisms from a common ancestor. 
C)  This is only true for repetitive DNA. 
D)  These organisms are always very closely related, as with chimpanzees and humans. 
E)  Identical sections of DNA will always perform the same function, regardless of the organisms in which they are found. 
A)  This DNA is usually non-functional. 
B)  This constitutes evidence of evolution of these organisms from a common ancestor. 
C)  This is only true for repetitive DNA. 
D)  These organisms are always very closely related, as with chimpanzees and humans. 
E)  Identical sections of DNA will always perform the same function, regardless of the organisms in which they are found.

Question 19

A coding sequence is translated into a functional peptide via a

Accepted Answer

A)  protein. 
B)  mRNA intermediate. 
C)  polycistronic message. 
D)  tRNA intermediate. 
E)  coding sequences code for a transcript only, not a peptide. 
A)  protein. 
B)  mRNA intermediate. 
C)  polycistronic message. 
D)  tRNA intermediate. 
E)  coding sequences code for a transcript only, not a peptide.

Question 20

The percentage of essential genes in a genome, as measured in the laboratory, is probably an underestimate because

Accepted Answer

A)  many genes are only essential in poor conditions, not simulated in the laboratory. 
B)  the functions of many genes are, as yet, poorly understood. 
C)  some genes are expressed at such low levels that they are not easily detected. 
D)  All of the answers are correct 
E)  None of the answers are correct 
A)  many genes are only essential in poor conditions, not simulated in the laboratory. 
B)  the functions of many genes are, as yet, poorly understood. 
C)  some genes are expressed at such low levels that they are not easily detected. 
D)  All of the answers are correct 
E)  None of the answers are correct

Exam 13: Genomes, Mutation and Cancer

The dominant oncogene, ras

A tumorous cell is not a cancer because

Barley has a genome of 5.3 Gb. This is the same as

Excision repair only works because

Spontaneous mutations

The genome of a virus is composed of

Variation between individuals of a species

Transposons are

Organelle genomes

To manufacture DNA, the cell needs a balance in the levels of purine and pyrimidine nucleotides. This balance is controlled by

Which of the following statements about chloroplast chromosomes is CORRECT?

Which of the following statements about DNA is CORRECT?

Non-coding DNA can best be described as

Humans have

A tumour suppression gene is

Which of the following statements is CORRECT?

Which of the following statements is true?

Given that different organisms can have sections of DNA that are almost identical, which of the following statements is CORRECT?

A coding sequence is translated into a functional peptide via a

The percentage of essential genes in a genome, as measured in the laboratory, is probably an underestimate because

Nature of Molecules

Biomolecules

The Chemistry of Life

Functioning Cells

Movement Across Membranes

Harvesting Energy

Cells, Tissues and Signals

Cell Division

Inheritance

Genes, Chromosomes and Dna

The Genetic Code

Gene Expression

Viruses

Genetic Engineering and Biotechnology

Reproduction, Growth and Development of Flowering Plants

Structure of Plants

Plant Nutrition, Transport and Adaptation to Stress

Plant Hormones and Growth Responses

Animal Reproduction

Animal Development

Homeostasis: Water, Solutes and Excretion

Gas Exchange in Animals

Circulation

Metabolism, Temperature Regulation and Environmental Stress

Animal and Human Nutrition

Innate Defences and the Immune System

Hormonal Control in Animals

Nervous Systems

Animal Movement

Animal Behaviour

Evolving Life

Evolving Earth

Mechanisms of Evolution

Bacteria

The Protists

Plants

Fungi

Simple Animals: Sponges to Flatworms

Annelids, Molluscs, Nematodes and Arthropods

Echinoderms and Chordates

Australian Biota

Population Ecology

Living in Communities

Ecosystems

Human Impacts

Filters