Question 1

Which of the following observations from Mendel's pea plant experiments most directly contradicted the idea of blending inheritance?

Accepted Answer

The F2 generation included individuals with traits identical to one of the original parent strains.

Question 2

In a monohybrid cross between two heterozygous pea plants (Pp x Pp), what is the expected genotypic ratio among the F2 offspring?

Accepted Answer

$$1:2:1$$

Question 3

Which principle states that alleles for a gene segregate during gamete formation and are rejoined at random during fertilization?

Accepted Answer

Principle of Segregation

Question 4

A dihybrid cross between two pea plants heterozygous for both seed color and seed shape (RrYy x RrYy) produces which phenotypic ratio in the F2 generation?

Accepted Answer

$$9:3:3:1$$

Question 5

Which of the following best explains the principle of independent assortment?

Accepted Answer

Alleles for different genes segregate independently due to the random alignment of homologous chromosomes during metaphase I of meiosis.

Question 6

If a plant with genotype P_ (unknown if PP or Pp) is testcrossed with a pp plant and all offspring have purple flowers, what is the genotype of the unknown parent?

Accepted Answer

PP

Question 7

In a cross between two heterozygous individuals (Aa x Aa), what is the probability that an offspring will be homozygous recessive (aa)?

Accepted Answer

$$1/4$$

Question 8

Which of the following is an example of codominance in humans?

Accepted Answer

ABO blood group, where both IA and IB alleles are expressed in the AB blood type

Question 9

Which genetic phenomenon is illustrated when a single gene affects multiple, seemingly unrelated phenotypic traits, as seen in cystic fibrosis?

Accepted Answer

Pleiotropy

Question 10

A Himalayan rabbit has dark fur on its ears, nose, and feet, but white fur elsewhere. This is an example of which genetic concept?

Accepted Answer

Environmental influence on phenotype

Question 11

Which of the following best describes polygenic inheritance?

Accepted Answer

Multiple genes contribute additively to a single trait, resulting in continuous variation

Question 12

In Labrador retrievers, coat color is determined by two genes, and the presence of one gene can mask the expression of the other. This is an example of:

Accepted Answer

Epistasis

Question 13

Which of the following statements about heritability is correct?

Accepted Answer

Narrow sense heritability ($$h^2) $$measures the fraction of phenotypic variation due to additive genetic variance.

Question 14

Which of the following is NOT an assumption of Mendel's model of inheritance?

Accepted Answer

Genes are always influenced by environmental factors.

Question 15

A cross between a red-flowered plant and a white-flowered plant produces all pink-flowered offspring. When these pink-flowered plants are self-crossed, what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

$$1$$ red : $$2$$ pink : $$1$$ white

Question 16

Which of the following best describes the genetic basis of human ABO blood types?

Accepted Answer

Multiple alleles and codominance

Question 17

If the probability of inheriting allele A from one parent is $$1/2$$ and from the other parent is $$1/2$$, what is the probability that an offspring will be AA?

Accepted Answer

$$1/4$$

Question 18

Which of the following scenarios demonstrates the rule of addition in probability?

Accepted Answer

Calculating the probability of getting either Pp or pP genotype in a cross

Question 19

Which of the following is an example of incomplete dominance?

Accepted Answer

A cross between red and white flowers producing pink flowers

Question 20

Which of the following is true regarding alleles?

Accepted Answer

An individual can have only two alleles for a given gene, but more than two alleles may exist in a population.

Chapter 12: Patterns of Inheritance – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard