Question 1

Which of the following best describes the relationship between genotype and phenotype?

Accepted Answer

Genotype is the genetic makeup of an organism, and phenotype is the observable expression of that genotype.

Question 2

A plant with genotype $$Pp is $$crossed with a plant with genotype $$pp. $$What is the expected phenotypic ratio of the offspring if $$P is $$dominant for purple flowers and $$p is $$recessive for white flowers?

Accepted Answer

$$1$$ purple : $$1$$ white

Question 3

Which of the following statements about homologous chromosomes is correct?

Accepted Answer

They carry information for the same traits.

Question 4

In a dihybrid cross between two heterozygous pea plants ($$YyRr 	imes YyRr$$), what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

$$9:3:3:1$$

Question 5

A true-breeding dark-leaved plant ($$DD) is $$crossed with a light-leaved plant ($$dd). $$The F1 offspring are allowed to self-pollinate. What proportion of the F2 generation will have light green leaves?

Accepted Answer

$$\frac{1}{4}$$

Question 6

Which of the following best explains why Mendel continued his experiments into the F2 and F3 generations?

Accepted Answer

To determine whether a recessive trait would reappear.

Question 7

If a plant with genotype $$Uu ($$unattached earlobes, dominant) is crossed with a plant with genotype $$uu ($$attached earlobes, recessive), what is the expected genotypic ratio of the offspring?

Accepted Answer

$$1 Uu$$ : $$1 uu$$

Question 8

Which of the following is a significant conclusion that Gregor Mendel drew from his experiments with pea plants?

Accepted Answer

Traits are inherited in discrete units and are not the result of blending.

Question 9

A testcross is performed between a plant with an unknown genotype for purple flowers and a white-flowered plant ($$pp). If $$the offspring show a $$1:1$$ ratio of purple to white flowers, what is the genotype of the unknown plant?

Accepted Answer

Heterozygous ($$Pp)$$

Question 10

Which of the following best describes the law of independent assortment?

Accepted Answer

Each pair of alleles segregates independently of each other pair during gamete formation.

Question 11

In a cross between $$BbDD$$ and $$BBDd$$ individuals, assuming independent assortment, which of the following genotypic ratios would you expect in the offspring?

Accepted Answer

$$1$$ BBDD : $$1$$ BbDD : $$1$$ BBDd : $$1$$ BbDd

Question 12

A cross between a red cow and a white cow produces offspring with both red and white patches. What type of inheritance is this an example of?

Accepted Answer

Codominance

Question 13

If two organisms with genotype $$AaBb$$ are mated, what is the probability of obtaining an offspring with genotype $$AABB$$?

Accepted Answer

$$\frac{1}{16}$$

Question 14

Which of the following best describes an allele?

Accepted Answer

An alternative version of a gene that may produce distinguishable phenotypic effects.

Question 15

A tall plant with purple flowers is crossed with a dwarf plant with white flowers and produces $$50\%$$ tall, purple and $$50\%$$ tall, white progeny. What are the most likely genotypes of the parents?

Accepted Answer

TTPp 	imes ttpp

Question 16

Which rule of probability would you use to determine the probability that two independent events will both occur?

Accepted Answer

Multiplication rule

Question 17

In a testcross, if all offspring display the dominant phenotype, what can you conclude about the genotype of the tested parent?

Accepted Answer

It is homozygous dominant.

Question 18

Which of the following best describes the law of segregation?

Accepted Answer

It describes the inheritance of different alleles relative to one another.

Question 19

A plant with genotype $$Dd is $$self-pollinated. What is the probability that an offspring will be homozygous recessive?

Accepted Answer

$$\frac{1}{4}$$

Genetics and Mendelian Inheritance: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards