Mendelian Genetics: Learn the Basics of Inheritance

Question 1

Which of the following best describes a heterozygous genotype?

Accepted Answer

Contains two different alleles

Answer

Contains two identical alleles

Answer

Always results in a dominant phenotype

Answer

Always results in a recessive phenotype

Question 2

In a monohybrid cross, what is the probability of inheriting a dominant allele from a heterozygous parent?

Accepted Answer

50%

Answer

0%

Answer

25%

Answer

75%

Question 3

Which of the following is NOT one of Gregor Mendel's proposed laws of genetics?

Accepted Answer

Law of Incomplete Dominance

Answer

Law of Segregation

Answer

Law of Independent Assortment

Answer

Law of Dominance

Question 4

In a monohybrid cross between a homozygous dominant plant (AA) and a homozygous recessive plant (aa), what is the expected phenotype of the F1 generation?

Accepted Answer

All dominant phenotype

Answer

All recessive phenotype

Answer

Both dominant and recessive phenotypes

Answer

Neither dominant nor recessive phenotype

Question 5

What term refers to the observable physical and biochemical characteristics of an organism that result from its genotype?

Accepted Answer

Phenotype

Answer

Genotype

Answer

Allele

Answer

Locus

Question 6

Which of Mendel's experiments provided evidence for the Law of Independent Assortment?

Accepted Answer

Dihybrid crosses

Answer

Monohybrid crosses

Answer

Test crosses

Answer

Backcrosses

Question 7

What is the term for the complete set of genes carried by an individual?

Accepted Answer

Genome

Answer

Genotype

Answer

Phenotype

Answer

Karyotype

Question 8

How do the laws of segregation and independent assortment contribute to genetic diversity in offspring?

Accepted Answer

They ensure that each gamete carries only one allele for each gene, and the alleles of different genes assort independently during gamete formation.

Answer

They determine the probability of inheriting specific alleles from both parents.

Answer

They ensure that recessive alleles are not expressed in the offspring.

Answer

They are responsible for the inheritance of traits that show a continuous variation.

Question 9

Define the terms 'homozygous' and 'heterozygous' as they relate to genotypes and provide an example of each.

Accepted Answer

A homozygous genotype has two identical alleles for a particular gene, while a heterozygous genotype has two different alleles for the same gene.

Answer

A homozygous genotype is always dominant, while a heterozygous genotype is always recessive.

Answer

Heterozygous genotypes are only found in males, while homozygous genotypes are only found in females.

Answer

Homozygous genotypes are always expressed, while heterozygous genotypes are never expressed.

Question 10

Why is Gregor Mendel considered the father of genetics?

Accepted Answer

Mendel's experiments with pea plants led to the discovery of the laws of inheritance.

Answer

Mendel invented the microscope.

Answer

Mendel's work was based on the idea of natural selection.

Answer

Mendel's theories have been completely disproven by modern genetics.

Question 11

What is the scientific term for an alternative form of a gene?

Accepted Answer

Allele

Answer

Phenotype

Answer

Genotype

Answer

Dominance

Question 12

In an individual carrying both dominant and recessive alleles of a particular gene, which allele determines the visible characteristics, known as the phenotype?

Accepted Answer

Dominant allele

Answer

Recessive allele

Answer

Neither allele

Answer

Both alleles

Question 13

In a cross between parents who are both heterozygous for a particular gene, what is the probability of their offspring inheriting two recessive alleles?

Accepted Answer

25%

Answer

0%

Answer

50%

Answer

75%

Question 14

Which of the following laws proposed by Gregor Mendel states that each gamete, such as an egg or sperm, carries only one copy of each gene?

Accepted Answer

Law of Segregation

Answer

Law of Independent Assortment

Answer

Law of Dominance

Answer

Law of Probability

Question 15

What is the term used to describe the observable, physical or chemical characteristics of an organism?

Accepted Answer

Phenotype

Answer

Genotype

Answer

Allele

Answer

Gene

Question 16

Which of the following terms describes the transfer of genetic material from parents to their offspring?

Accepted Answer

Inheritance

Answer

Mutation

Answer

Natural selection

Answer

Mitosis

Question 17

Which of the following is NOT a fundamental law of Mendelian genetics?

Accepted Answer

Law of Molecular Biology

Answer

Law of Independent Assortment

Answer

Law of Dominance

Answer

Law of Segregation

Question 18

When both dominant and recessive alleles are present in an individual, which allele is expressed?

Accepted Answer

Dominant

Answer

Recessive

Answer

Both equally

Answer

Neither

Question 19

Which of the following is a defining characteristic of a testcross?

Accepted Answer

One parent has a homozygous recessive genotype.

Answer

Both parents have the same phenotype.

Answer

The offspring will all be heterozygous.

Answer

The offspring will exhibit a 3:1 phenotype ratio.

Question 20

What is the probability of obtaining a homozygous recessive individual from a heterozygous parent?

Accepted Answer

25%

Answer

0%

Answer

50%

Answer

75%

Question 21

Which of the following traits is an example of polygenic inheritance?

Accepted Answer

Height

Answer

Eye color

Answer

Blood type

Answer

Skin color

Question 22

What is the term for the allele that is masked in the phenotype when both dominant and recessive alleles are present?

Accepted Answer

Recessive

Answer

Dominant

Answer

Co-dominant

Answer

Incomplete Dominant

Question 23

Which of the following is NOT a type of Mendelian inheritance pattern?

Accepted Answer

Mitochondrial

Answer

Autosomal Dominant

Answer

Autosomal Recessive

Answer

X-Linked Dominant

Question 24

What is the difference between genotype and phenotype?

Accepted Answer

Genotype is the genetic makeup, while phenotype is the observable traits.

Answer

Genotype is the observable traits, while phenotype is the genetic makeup.

Answer

They are the same thing.

Answer

Genotype is the expression of genes, while phenotype is the alleles.

Question 25

Who is known as the "Father of Genetics"?

Accepted Answer

Gregor Mendel

Answer

Charles Darwin

Answer

James Watson

Answer

Francis Crick

Question 26

Which of the following is the basic unit of heredity that carries genetic information?

Accepted Answer

Gene

Answer

Chromosome

Answer

Allele

Answer

Trait

Question 27

In an individual with two different alleles for a trait (heterozygous), which allele is observable in the phenotype?

Accepted Answer

Dominant

Answer

Recessive

Answer

Both dominant and recessive

Answer

Neither dominant nor recessive

Question 28

What is the probability of obtaining an offspring with both recessive alleles (homozygous recessive) from parents who both carry one dominant and one recessive allele (heterozygous)?

Accepted Answer

25%

Answer

0%

Answer

50%

Answer

75%

Question 29

Which principle of genetics explains that alleles of different genes separate independently during the formation of gametes (sex cells)?

Accepted Answer

Law of Independent Assortment

Answer

Law of Segregation

Answer

Law of Dominance

Answer

Law of Recessiveness

Question 30

Which of the following is not considered a mechanism for genetic variation?

Accepted Answer

Natural selection

Answer

Mutation

Answer

Recombination

Answer

Gene duplication

Question 31

What is the primary purpose of a pedigree chart in genetics?

Accepted Answer

To trace the inheritance of traits within a family

Answer

To predict the chance of developing a specific disease

Answer

To identify specific genetic mutations

Answer

To determine the exact genotype of an individual

Question 32

Which laboratory technique is used to separate fragments of DNA based on their size?

Accepted Answer

Gel electrophoresis

Answer

PCR

Answer

Restriction enzyme digestion

Answer

DNA sequencing

Question 33

Which of the following best defines the term 'allele'?

Accepted Answer

Different forms of a gene

Answer

Location of a gene on a chromosome

Answer

Dominant or recessive trait

Answer

Type of DNA molecule

Question 34

In a heterozygous individual, which of the following combinations of alleles are present?

Accepted Answer

One dominant and one recessive allele

Answer

Two dominant alleles

Answer

Two recessive alleles

Answer

One allele for each gene

Question 35

In a monohybrid cross involving heterozygous parents, what is the probability of obtaining offspring with homozygous dominant genotypes?

Accepted Answer

25%

Answer

0%

Answer

50%

Answer

100%

Question 36

A key feature of the law of independent assortment is that:

Accepted Answer

Alleles for different genes separate independently during meiosis

Answer

Alleles for the same gene always separate together

Answer

Dominant alleles are always expressed

Answer

Recessive alleles are always expressed

Question 37

In a Punnett square, what do the letters arranged along the top and side of the square represent?

Accepted Answer

Alleles of the parents

Answer

Genotypes of the parents

Answer

Phenotypes of the parents

Answer

Possible genotypes of the offspring

Question 38

Which of the following terms describes an organism that has two different alleles for a particular gene?

Accepted Answer

Heterozygous

Answer

Homozygous dominant

Answer

Homozygous recessive

Answer

Hybrid

Question 39

Which of the following techniques is commonly used to study inheritance patterns of traits?

Accepted Answer

Pedigree analysis

Answer

Karyotyping

Answer

Gel electrophoresis

Answer

Microscopy

Question 40

Which of the following genotypes represents a heterozygous individual?

Accepted Answer

Aa

Answer

aa

Answer

AA

Answer

a

Question 41

According to Mendel's Law of Segregation, what happens to alleles during gamete formation?

Accepted Answer

They separate into different gametes.

Answer

They are inherited in equal proportions from both parents.

Answer

They combine to form a dominant allele.

Question 42

What is the probability of obtaining a homozygous recessive offspring from two heterozygous parents?

Accepted Answer

25%

Answer

50%

Answer

100%

Answer

0%

Question 43

Who is known as the 'Father of Genetics' for his discovery of the laws of heredity?

Accepted Answer

Gregor Mendel

Answer

Charles Darwin

Answer

Louis Pasteur

Answer

James Watson

Question 44

What term describes the observable characteristics of an organism?

Accepted Answer

Phenotype

Answer

Genotype

Answer

Allele

Answer

Locus

Question 45

What is the purpose of using a Punnett square?

Accepted Answer

To predict the possible genotypes and phenotypes of offspring.

Answer

To demonstrate the Law of Independent Assortment.

Answer

To trace the inheritance of a specific gene.

Question 46

Which of the following genotypes represents a homozygous individual?

Accepted Answer

TT

Answer

T

Answer

Tt

Answer

tt

Question 47

What term refers to different versions of a gene?

Accepted Answer

Alleles

Answer

Phenotypes

Answer

Traits

Answer

Genotypes

Question 48

Which of the following represents the correct order of dominance in Mendelian inheritance?

Accepted Answer

Homozygous dominant > Heterozygous > Homozygous recessive

Answer

Heterozygous > Homozygous dominant > Homozygous recessive

Answer

Homozygous recessive > Heterozygous > Homozygous dominant

Question 49

A purple-flowered plant with homozygous dominant alleles (PP) is crossed with a white-flowered plant with homozygous recessive alleles (pp). What will be the genotype of all their offspring?

Accepted Answer

Pp

Answer

PP

Answer

PPP

Answer

pp

Question 50

Two pea plants, each carrying one dominant (R) and one recessive (r) allele for seed shape, are crossed (Rr x Rr). What is the chance their offspring will have the recessive trait (rr) and produce wrinkled seeds?

Accepted Answer

25%

Answer

50%

Answer

100%

Answer

75%

Question 51

Which statement about Mendelian genetics is NOT true?

Accepted Answer

Genes for different traits are always inherited together.

Answer

Each organism has two copies of each gene.

Answer

Alleles separate during the formation of gametes.

Question 52

A woman with blood type A (IAi) has a child with a man who has blood type B (IBi). What are the possible blood types of their children?

Accepted Answer

A, B, AB, and O

Answer

AB and O only

Answer

A and B only

Question 53

A purple-flowered plant (PP) is crossed with a white-flowered plant (pp), and all their offspring have purple flowers. What does this tell us about the flower color alleles?

Accepted Answer

The purple flower allele is dominant over the white flower allele.

Answer

The white flower allele is dominant over the purple flower allele.

Answer

The purple flower allele is recessive.

Answer

Purple and white flower alleles are codominant.

Question 54

Which of Mendel's laws explains why traits like seed shape and flower color are inherited independently of each other?

Accepted Answer

Law of Independent Assortment

Answer

Law of Probability

Answer

Law of Dominance

Answer

Law of Segregation

Question 55

A scientist studying a fruit fly population finds that 20% of the alleles for a specific trait are recessive. What percentage of the alleles in this population are dominant?

Accepted Answer

80%

Answer

20%

Answer

40%

Question 56

Two parents are carriers for cystic fibrosis, a recessive genetic disorder. What is the chance that their child will inherit the disorder?

Accepted Answer

25%

Answer

75%

Answer

50%

Answer

100%

Question 57

What is a test cross used for?

Accepted Answer

To determine the genotype of an individual with an unknown genotype by crossing it with a homozygous recessive individual.

Answer

To cross two individuals with different phenotypes.

Answer

To cross two individuals with the same genotype.