Inheritance, Variation and Evolution Quizzes - Biology Year 12

Question 1

Which of the following is NOT a mechanism that directly contributes to genetic variation within a population?

Accepted Answer

Natural selection

Answer

Mutation

Answer

Genetic recombination

Answer

Gene flow

Question 2

Which enzyme is responsible for separating the DNA strands during replication?

Accepted Answer

Helicase

Answer

DNA polymerase

Answer

RNA polymerase

Answer

Ligase

Question 3

What is the main role of RNA polymerase in transcription?

Accepted Answer

Adding RNA nucleotides to the growing RNA chain

Answer

Unwinding the DNA double helix

Answer

Joining RNA nucleotides together

Answer

Proofreading the RNA molecule

Question 4

How does DNA methylation affect gene expression? Give an example of epigenetic inheritance involving this mechanism.

Accepted Answer

DNA methylation inhibits gene expression by blocking transcription factors from binding to the promoter region.

Answer

DNA methylation promotes gene expression by attracting histone acetyltransferases, which loosen the chromatin structure.

Answer

DNA methylation has no effect on gene expression because it only occurs in non-coding regions of the genome.

Answer

DNA methylation is an example of genetic inheritance, not epigenetic inheritance, because it involves changes to the DNA sequence.

Question 5

How do mutations contribute to genetic variation and drive evolution?

Accepted Answer

Mutations play a significant role in creating genetic diversity and influencing the process of evolution.

Answer

Mutations always have negative effects and never provide any benefits.

Answer

Mutations only happen in reproductive cells and are always passed on to offspring.

Question 6

How does genetic drift affect small populations? Which of these factors contribute to this process?

Accepted Answer

Population size and founder effects

Answer

Gene flow and mutation rates

Answer

Natural selection and genetic drift

Answer

Population density and genetic engineering

Question 7

Which factor has the greatest impact on the speed of genetic drift in a population?

Accepted Answer

Population size

Answer

Mutation rate

Answer

Strength of natural selection

Answer

Gene flow

Question 8

How does meiosis contribute to genetic variation?

Accepted Answer

Random assortment of homologous chromosomes during metaphase I

Accepted Answer

Crossing over during prophase I

Answer

Meiosis produces diploid gametes

Answer

Meiosis does not contribute to genetic variation

Question 9

What is adaptive radiation?

Accepted Answer

The process where a single species evolves into multiple species that occupy different habitats and exhibit unique adaptations.

Answer

The gradual change in a population's gene pool over time due to random genetic drift.

Answer

The process by which beneficial mutations increase in frequency within a population due to natural selection.

Answer

The process where new species are formed through the interbreeding of existing species.

Question 10

Propose a hypothesis that explains how natural selection could contribute to the development of antibiotic resistance in bacteria.

Accepted Answer

Antibiotic resistance offers bacteria an advantage, enabling them to survive and reproduce in antibiotic-rich environments, resulting in their increased prevalence.

Answer

Antibiotic resistance is a random event unaffected by natural selection or bacterial survival rates.

Answer

Antibiotics eliminate all bacteria, preventing the emergence and spread of antibiotic resistance.

Answer

Antibiotic resistance is caused by mutations that universally harm bacterial fitness.

Question 11

In a plant population that follows the Hardy-Weinberg equilibrium, the frequency of the dominant allele (A) is 0.6. What is the frequency of the homozygous recessive genotype (aa)?

Accepted Answer

0.16

Answer

0.25

Answer

0.36

Answer

0.49

Question 12

How do RNA polymerase and transcription factors contribute to the initiation of transcription?

Accepted Answer

RNA polymerase binds to promoters, and transcription factors enhance its binding and initiate transcription.

Answer

RNA polymerase synthesizes RNA in the 3' to 5' direction, and transcription factors terminate transcription.

Answer

Transcription factors bind to enhancers, and RNA polymerase enhances their binding.

Answer

RNA polymerase synthesizes RNA in the 5' to 3' direction, and transcription factors initiate transcription.

Question 13

Which of the following enzymes is NOT involved in the process of DNA replication?

Accepted Answer

Transcriptase

Answer

Helicase

Answer

Polymerase

Answer

Ligase

Question 14

The genetic code is read in groups of three nucleotides, known as:

Accepted Answer

Codons

Answer

Anticodons

Answer

Promoters

Answer

Terminators

Question 15

The theory of evolution by natural selection states that individuals with traits that are more:

Accepted Answer

Advantageous will have a greater chance of survival and reproduction

Answer

Less advantageous will be more likely to survive and reproduce

Answer

Equally advantageous will have an equal chance of survival and reproduction

Answer

Disadvantageous will have a greater chance of survival and reproduction

Question 16

The process by which a gene is copied into messenger RNA (mRNA) is called:

Accepted Answer

Transcription

Answer

Replication

Answer

Translation

Answer

Mutation

Question 17

A population of rabbits is isolated on an island. Over time, the rabbits adapt to their limited food supply by evolving smaller body sizes. This is an example of:

Accepted Answer

Directional selection

Answer

Stabilizing selection

Answer

Disruptive selection

Answer

Artificial selection

Question 18

The Human Genome Project was a:

Accepted Answer

Collaboration of scientists to map the entire human genome

Answer

Effort to clone the first human being

Answer

Government program to improve healthcare

Answer

Private sector initiative to develop new drugs

Question 19

Which of the following is NOT a mechanism of genetic variation within a population?

Accepted Answer

Epigenetics

Answer

Mutation

Answer

Recombination

Answer

Gene duplication

Question 20

The process by which DNA is faithfully copied into a complementary RNA molecule is known as:

Accepted Answer

Transcription

Answer

Replication

Answer

Translation

Answer

Mitosis

Question 21

Which of the following represents the correct sequence of nitrogenous bases in an mRNA molecule?

Accepted Answer

TACG

Answer

ATGC

Answer

TGAC

Answer

CGTA

Question 22

Which of the following is an example of a homologous structure?

Accepted Answer

The wings of a bird and the wings of a bat

Answer

The legs of a dog and the legs of a cat

Answer

The eyes of a human and the eyes of a fish

Answer

The hair of a mammal and the feathers of a bird

Question 23

Which of the following is a genetic disorder caused by a mutation in a single gene?

Accepted Answer

Sickle cell anaemia

Answer

Type 2 diabetes

Answer

Cancer

Answer

Alzheimer's disease

Question 24

What is the term for the hypothetical organism from which all living organisms are believed to have evolved?

Accepted Answer

Last universal common ancestor

Answer

Universal ancestor

Answer

Mitochondrial Eve

Answer

Y-chromosomal Adam

Question 25

What is the term for the study of the distribution and abundance of organisms?

Accepted Answer

Biogeography

Answer

Ecology

Answer

Evolution

Answer

Taxonomy

Question 26

In DNA, which sequence of nitrogenous bases is correct?

Accepted Answer

Adenine-Thymine-Cytosine-Guanine

Answer

Adenine-Cytosine-Guanine-Uracil

Answer

Guanine-Cytosine-Adenine-Thymine

Answer

Uracil-Cytosine-Guanine-Adenine

Question 27

During DNA replication, which enzyme unwinds the double helix?

Accepted Answer

Helicase

Answer

Polymerase

Answer

Ligase

Answer

Primase

Question 28

What process synthesizes RNA from a DNA template?

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Mutation

Question 29

Which theory explains the evolution of species?

Accepted Answer

Darwin's Theory of Natural Selection

Answer

Lamarck's Theory of Inheritance of Acquired Characteristics

Answer

Mendelian Genetics

Answer

The Gaia Hypothesis

Question 30

Which of these is an example of natural selection?

Accepted Answer

Organisms with favorable traits survive in their environment

Answer

Traits acquired during an organism's lifetime are inherited

Answer

The gradual change in a population's genetic makeup over time

Answer

Random occurrence of mutations

Question 31

Where does protein synthesis occur?

Accepted Answer

Ribosome

Answer

Nucleus

Answer

Mitochondria

Answer

Golgi apparatus

Question 32

Which of these is NOT a characteristic of genetic variation?

Accepted Answer

Always beneficial

Answer

Essential for evolution

Answer

Can be continuous or discontinuous

Answer

Influenced by the environment

Question 33

What is the difference between genotype and phenotype?

Accepted Answer

Genotype is genetic makeup, phenotype is observable characteristics

Answer

Phenotype is genetic makeup, genotype is observable characteristics

Answer

Genotype and phenotype are the same

Answer

There is no difference between genotype and phenotype

Question 34

Which nitrogenous base pairs with adenine in DNA?

Accepted Answer

Thymine

Answer

Cytosine

Answer

Guanine

Answer

Uracil

Question 35

Which process involves the synthesis of RNA using a DNA template?

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Mutation

Question 36

Which type of mutation adds an additional nucleotide to a gene sequence?

Accepted Answer

Insertion

Answer

Deletion

Answer

Substitution

Answer

Translocation

Question 37

What is the term for the process where DNA is copied?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 38

What is the role of natural selection in evolution?

Accepted Answer

Selecting for the survival and reproduction of advantageous traits.

Answer

Creating new genetic variation.

Answer

Introducing mutations in DNA.

Answer

Preventing the extinction of species.

Question 39

How do a genotype and a phenotype differ?

Accepted Answer

Genotype refers to an organism's genetic makeup, while phenotype refers to its observable characteristics.

Answer

Phenotype refers to an organism's genetic makeup, while genotype refers to its observable characteristics.

Answer

Genotype and phenotype represent the same concept.

Answer

Neither of the above.

Question 40

How can homologous and analogous structures be differentiated?

Accepted Answer

Homologous structures share a common evolutionary origin, while analogous structures do not, despite similar functions.

Answer

Homologous structures do not share a common evolutionary origin, while analogous structures do, despite similar functions.

Answer

Homologous and analogous structures are identical.

Answer

Neither of the above.

Question 41

Which of the following is the correct sequence of stages in DNA replication?

Accepted Answer

Initiation, Elongation, Termination

Answer

Transcription, Translation, Initiation

Answer

Elongation, Initiation, Termination

Answer

Replication, Transcription, Translation

Question 42

What is the primary mechanism driving evolution by natural selection?

Accepted Answer

Favoring individuals with advantageous traits that increase their survival and reproductive success

Answer

Eliminating individuals with harmful traits

Answer

Creating entirely new species

Answer

Accelerating the pace of genetic change

Question 43

What is the primary distinction between genotype and phenotype?

Accepted Answer

Genotype refers to an organism's genetic makeup, while phenotype refers to its observable characteristics

Answer

Phenotype refers to an organism's genetic makeup, while genotype refers to its observable characteristics

Answer

There is no meaningful distinction between genotype and phenotype

Answer

Both genotype and phenotype measure an organism's fitness

Question 44

Which of the following processes involves the synthesis of RNA from a DNA template?

Accepted Answer

Transcription

Answer

Replication

Answer

Translation

Answer

Mutation

Question 45

Which nitrogenous base is NOT found in DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Thymine

Answer

Cytosine

Question 46

The process by which DNA molecules are duplicated is called:

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 47

Which enzyme is responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Answer

Primase

Answer

DNA polymerase

Answer

Ligase

Question 48

What is the primary role of the ribosome in protein synthesis?

Accepted Answer

To assemble amino acids into a polypeptide chain

Answer

To unwind the DNA double helix

Answer

To catalyze the formation of peptide bonds

Answer

To synthesize mRNA

Question 49

Which of the following is NOT a factor that can influence the rate of evolution?

Accepted Answer

Environmental stability

Answer

Mutation rate

Answer

Population size

Answer

Migration rate

Question 50

The theory of endosymbiosis proposes that:

Accepted Answer

Mitochondria and chloroplasts originated from free-living bacteria

Answer

Eukaryotic cells evolved from the fusion of prokaryotic cells

Answer

The nucleus evolved from the endoplasmic reticulum

Answer

Cells originated from non-living matter

Question 51

DNA replication is the process by which:

Accepted Answer

DNA is copied to form two identical molecules

Answer

DNA is transcribed into RNA

Answer

RNA is translated into protein

Answer

Protein is folded into a specific shape

Question 52

What is the main function of a codon in protein synthesis?

Accepted Answer

To specify the sequence of amino acids in a protein

Answer

To transport amino acids to the ribosome

Answer

To decode the genetic code

Answer

To catalyze the formation of peptide bonds

Question 53

Which of the following is NOT a characteristic of a population in Hardy-Weinberg equilibrium?

Accepted Answer

Genotype frequencies may change over time

Answer

Allele frequencies do not change from generation to generation

Answer

There is no evolution occurring

Answer

Mating is random

Question 54

Which of the following is NOT a possible consequence of a mutation?

Accepted Answer

Improved fitness of the organism carrying the mutation

Answer

Altered protein function

Answer

Change in gene expression

Answer

Creation of a new allele

Question 55

What is the primary role of homologous chromosomes during meiosis?

Accepted Answer

To facilitate genetic recombination

Answer

To ensure independent assortment

Answer

To determine the sex of the offspring

Answer

To prevent inbreeding

Question 56

What is the primary role of RNA polymerase in transcription?

Accepted Answer

To join RNA nucleotides together

Answer

To unwind the DNA double helix

Answer

To cut the DNA double helix

Answer

To proofread the newly synthesized RNA

Question 57

According to the principles of natural selection, which of the following individuals is most likely to survive and reproduce successfully?

Accepted Answer

An individual with a beneficial mutation

Answer

An individual with a harmful mutation

Answer

An individual with a neutral mutation

Answer

An individual with a lethal mutation

Question 58

What is the term for the change in the frequency of alleles or genotypes within a population over successive generations?

Accepted Answer

Evolution

Answer

Genetic drift

Answer

Mutation

Answer

Gene flow

Question 59

Which of the following is a defining characteristic of a homozygous genotype?

Accepted Answer

Is identical by descent

Answer

Has two different alleles for a gene

Answer

Produces gametes with both alleles

Answer

Produces a phenotype that is intermediate between the two alleles

Question 60

What is the probability of a heterozygous parent producing a gamete with the dominant allele during meiosis?

Accepted Answer

50%

Answer

0%

Answer

75%

Answer

100%

Question 61

Which of the following is NOT a mechanism that contributes to genetic variation within a population?

Accepted Answer

Natural selection

Answer

Independent assortment

Answer

Chromosomal crossover

Answer

Gene duplication

Question 62

What type of molecule primarily comprises the genetic material of viruses?

Accepted Answer

DNA and/or RNA

Answer

DNA only

Answer

RNA only

Answer

Protein

Question 63

Identify the enzyme responsible for unwinding the DNA double helix during DNA replication.

Accepted Answer

C. Helicase

Answer

A. DNA polymerase

Answer

B. RNA polymerase

Answer

D. Ligase

Question 64

What is the primary driving force behind the process of evolution by natural selection?

Accepted Answer

C. Differential survival and reproduction

Answer

A. Overproduction of offspring

Answer

B. Competition for limited resources

Answer

D. Random genetic variation