Mendelian and Non-Mendelian Inheritance

Autosomal Recessive

1. What is the inheritance pattern of Mendelian traits?

a. Polygenic inheritance

b. Autosomal recessive

c. Codominance

d. Multifactorial

Cystic Fibrosis

2. Which of the following genetic disorders follows a

Mendelian autosomal recessive inheritance pattern?

a. Huntington’s disease

b. Cystic fibrosis

c. Marfan syndrome

d. Achondroplasia

C

3. Incomplete dominance is a non-Mendelian

inheritance pattern where:

a. One allele is completely dominant over the

other.

b. Both alleles contribute equally to the phenotype.

c. The heterozygous phenotype is a blend of the

two homozygous phenotypes.

d. Two genes are involved in determining a single

trait.

B

4. Individuals with Marfan syndrome often exhibit tall

stature, long limbs, joint hypermobility, and a range of

cardiovascular, ocular, and skeletal abnormalities.

What gene is affected in individuals affected with this

disorder?

a. HBs gene

b. FBN1 gene

c. COL6A1 gene

d. ELN gene

A

5. The ABO blood group system is an example of:

a. Codominance

b. Incomplete dominance

c. X-linked inheritance

d. Polygenic inheritance

C

6. The family pedigree of Queen Victoria shows a

number of hemophilic descendants. Which of the

following statements would be probably TRUE?

a. She herself has hemophilia

b. c. d. Hemophilia is an autosomal recessive disorder

She is a carrier of hemophilia.

Hemophilia is caused by contact and therefore it

was seen in the royal family descendants

D

7. Cystic fibrosis is a genetic disorder caused by

mutations in the CFTR gene. Which of the following

best describes the primary impact of these mutations?

a. An impaired blood clotting

b. Abnormal cell division

c. Altered immune system function

d. Dysregulation of ion transport channels

D

8. If a trait is determined by multiple genes and

influenced by environmental factors, it is known as?

a. Pleiotropy

b. Polygenic inheritance

c. Codominance

d. Multifactorial

D

9.1 In humans, the ability to roll the tongue is a

dominant trait (R), while the inability to roll the tongue

is recessive (r). If a person who can roll their tongue

(Rr) has a child with someone who can also roll their

tongue (Rr), what is the expected genotypic ratio of

their offspring?

a. 1:1

b. 3:1

c. 2:1

d. 1:2:1

B

9.2 In humans, the ability to roll the tongue is a

dominant trait (R), while the inability to roll the tongue

is recessive (r). If a person who can roll their tongue

(Rr) has a child with someone who can also roll their

tongue (Rr), what is the expected phenotypic ratio of

their offspring?

a. 1:1

b. 3:1

c. 2:1

d. 1:2:1

A

10. What is the probability of having a child with Sickle

cell anemia if both parents are carriers (heterozygous)

for the autosomal recessive gene?

a. 25%

b. 50%

c. 75%

d. 100%

Mendelian Inheritance

Refers to certain patterns of how traits are passed from parents to offspring.

True breeding

refers to the breeding of organisms in which parents produce offspring with traits identical to those of the parents.

P generation

True-breeding parents

F1 Generation

hybrid offspring of the P generation are called

Monohybrid cross

A cross between such heterozygotes is called

A

1. In Mendel's experiments with pea plants, the law of

independent assortment states that:

a. Genes located on the same chromosome always

assort independently during gamete formation.

b. Genes located on different chromosomes segregate

independently during gamete formation.

c. Genes located on the same chromosome always

exhibit complete linkage.

d. Genes located on different chromosomes always

exhibit complete linkage.

B

2. What is the inheritance pattern of Mendelian traits?

a. Polygenic inheritance

b. Autosomal recessive

c. Codominance

d. Multifactorial

B

3. According to Mendel's law of segregation, alleles for

a trait separate during:

a. Fertilization

b. Gamete formation

c. Zygote development

d. Somatic cell division

C

4. Incomplete dominance is a non-Mendelian

inheritance pattern where:

a. One allele is completely dominant over the

other.

b. Both alleles contribute equally to the phenotype.

c. The heterozygous phenotype is a blend of the

two homozygous phenotypes.

d. Two genes are involved in determining a single

trait.

C

5. The phenomenon of epistasis occurs when:

a. Genes that interact on one another is always from

different chromosomes

b. Genes on the same chromosome segregate

independently.

c. One gene influences the expression of another

gene.

d. Two genes are completely linked

A

6. The ABO blood group system is an example of:

a. Codominance

b. Incomplete dominance

c. X-linked inheritance

d. Polygenic inheritance

D

7. If a trait is determined by multiple genes and

influenced by environmental factors, it is known as?

a. Pleiotropy

b. Polygenic inheritance

c. Codominance

d. Multifactorial

D

8. The coat color of Siamese cats is an example of a

trait influenced by both genetics and the environment.

This phenomenon is known as:

a. Codominance

b. Incomplete dominance

c. Pleiotropy

d. Multifactorial

Hemophilia A and B

Blood clotting disorders.

Duchenne muscular dystrophy

A progressive muscle- wasting disorder.

Albinism

recessive condition characterized by a

lack of pigmentation in skin and hair

Cystic Fibrosis

results in defective or absent chloride transport channels in plasma

membranes, leading to a buildup of chloride ions

Tay-Sachs Disease

autosomal recessive disease caused by mutations in both alleles of a gene

(HEXA) on chromosome 15.

Hemophilia A

most common form and is caused by a deficiency or dysfunction of clotting factor VIII.

Hemophilia B

also known as Christmas disease, is caused by a deficiency or dysfunction of clotting factor IX

Achondroplasia

form of dwarfism caused by a rare dominant allele