Inheritance 2

Question 1

What is incomplete dominance?

Answer 1

A genetic situation where one allele does not completely dominate another, resulting in a third phenotype.

Question 2

What are the genotypes and phenotypes of a cross between a red flower and a white flower with red (R) having incomplete dominance over white (r)?

Answer 2

Genotype: 100% Rr
Phenotype: 100% pink

Question 3

What is codominance?

Answer 3

A genetic situation where both alleles in a heterozygote are fully expressed.

Question 4

What are the genotypes and phenotypes of the offspring when a black chicken (C^B) is crossed with a white chicken (C^W) when both black and white are codominant?

Answer 4

The offspring will express both dominant alleles at the same time.

Genotype: 100% C^B C^W
Phenotype: 100% black and white (blue)

Question 5

What are carriers in genetics?

Answer 5

Individuals that carry a recessive allele for a trait but do not express it.

Question 6

True or False: Males can be carriers of X-linked traits.

Answer 6

False

Question 7

Why can females be carriers of recessive alleles for X-linked traits?

Answer 7

Because they have two X chromosomes, allowing one to be recessive while the other is dominant.

Question 8

What are multiple alleles?

Answer 8

Genes that have more than just 2 alleles.

These alleles can exhibit various dominance relationships.

Question 9

What types of dominance can multiple alleles exhibit?

Answer 9

• Fully dominant
• Recessive
• Codominant
• Incompletely dominant
• Hierarchies of dominance

These relationships determine how traits are expressed.

Question 10

Give an example of a trait with multiple alleles

Answer 10

Blood types

Question 11

What type of antibodies does blood type A produce?

Answer 11

Antibodies against B antigens

This is important for blood transfusions.

Question 12

What type of antibodies does blood type B produce?

Answer 12

Antibodies against A antigens

This is crucial for compatibility in blood transfusions.

Question 13

What type of antibodies does blood type AB produce?

Answer 13

Antibodies against nothing

This blood type is known as the universal recipient.

Question 14

What type of antibodies does blood type O produce?

Answer 14

Antibodies against A and B antigens

This blood type is known as the universal donor.

Question 15

What is a pedigree?

Answer 15

A diagram showing the inheritance pattern over many generations.

Question 16

What are the three common patterns of inheritance?

Answer 16

• Autosomal Recessive Inheritance
• Autosomal Dominant Inheritance
• X-Linked Inheritance (recessive)

Question 17

In autosomal recessive inheritance, what must be true about the parents of an affected individual?

Answer 17

Both parents must be heterozygous (Bb) or homozygous recessive (bb)

Question 18

In autosomal recessive inheritance, how are males and females affected?

Answer 18

Males and females are affected in approximately equal numbers.

Question 19

What is the expected outcome for children of an affected parent in autosomal dominant inheritance?

Answer 19

Half of the children are expected to be affected.

Question 20

In autosomal dominant inheritance, does the trait skip generations?

Answer 20

No, it does not skip generations.

Question 21

True or False: In autosomal dominant inheritance, males and females are affected in equal numbers.

Answer 21

True

Question 22

Is father-to-son transmission possible in autosomal dominant inheritance?

Answer 22

Yes

Question 23

What is a characteristic feature of X-linked recessive inheritance?

Answer 23

• No father-to-son transmission
• Affected females are extremely rare
• The trait skips generations

Question 24

In X-linked recessive inheritance, who is predominantly affected?

Answer 24

Predominantly males are affected.

Question 25

Fill in the blank: In X-linked recessive inheritance, affected fathers transmit the trait to _______.

Answer 25

carrier daughters