Question 1

Which of the following best describes the outcome of mitosis in terms of chromosome number and genetic identity?

Accepted Answer

Two diploid cells, each genetically identical to the parent cell

Question 2

In Mendel’s monohybrid cross between true-breeding purple-flowered (WW) and white-flowered (ww) pea plants, what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

$$3:1$$

Question 3

A couple are both carriers for cystic fibrosis (Ff). What is the probability that, in four children, exactly three will be unaffected and one will be affected? Use the binomial theorem.

Accepted Answer

$$\left( \frac{4!}{3!1!} \right) \left( \frac{3}{4} \$$right)^3$$ \left( \frac{1}{4} \$$right)^1$$ = \frac{27}{64}$$

Question 4

Which of Mendel’s postulates explains why alleles for different traits are inherited independently if they are on different chromosomes?

Accepted Answer

Law of Independent Assortment

Question 5

A test cross is performed between a plant with a dominant phenotype (unknown genotype) and a homozygous recessive plant. If the unknown plant is heterozygous, what is the expected phenotypic ratio among the offspring?

Accepted Answer

$$1:1 ($$dominant:recessive)

Question 6

Which of the following is a key reason Mendel’s choice of pea plants contributed to his experimental success?

Accepted Answer

Pea plants can self-fertilize and cross-fertilize, allowing controlled matings

Question 7

In a dihybrid cross between two heterozygotes (YyRr x YyRr), what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

$$9:3:3:1$$

Question 8

Which statistical test is used to determine if observed genetic data fit an expected Mendelian ratio?

Accepted Answer

Chi-square test

Question 9

Given the chi-square formula $$\$$chi^2$$ = \sum \frac{(o-e)^2$}{e}$$, what does a $$p$$ value greater than $$0.05$$ indicate about your null hypothesis?

Accepted Answer

The observed deviation is likely due to chance, so the null hypothesis is not rejected

Question 10

A pedigree shows a trait skipping generations and appearing equally in both sexes. What is the most likely mode of inheritance?

Accepted Answer

Autosomal recessive

Question 11

If a plant with genotype Ww is self-fertilized, what is the probability that an offspring will be homozygous recessive?

Accepted Answer

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

Question 12

Which of the following best explains why loss-of-function alleles are often recessive?

Accepted Answer

One functional allele is sufficient to produce the dominant phenotype

Question 13

In a family of four children, what is the probability that two will be male and two will be female? Use the binomial theorem.

Accepted Answer

$$\frac{3}{8}$$

Question 14

Which of the following is NOT a feature of Mendel’s model organism that contributed to his success?

Accepted Answer

Uncontrolled mating

Question 15

If the observed data in a monohybrid cross are 760 dominant and 240 recessive out of 1000 total, what are the expected numbers for a 3:1 ratio?

Accepted Answer

Dominant: 750, Recessive: 250

Question 16

Which of the following best describes the product law (multiplication rule) in probability as applied to genetics?

Accepted Answer

The probability of two independent events both occurring is the product of their individual probabilities

Question 17

A trihybrid cross (AaBbCc x AaBbCc) produces how many different phenotypes, assuming simple dominance for each gene?

Accepted Answer

8

Question 18

Which of the following statements about pedigrees is TRUE?

Accepted Answer

Recessive traits often appear equally in both sexes and may skip generations

Question 19

If a couple are both carriers for an autosomal recessive disorder, what is the probability that at least one of their four children will be affected?

Accepted Answer

$$1 - \left( \frac{3}{4} \$$right)^4$$

Mendelian Genetics: Principles, Probability, and Pedigree Analysis

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