Question 1

Which of the following is a specific experimental advantage of Mendel’s choice of pea plants as a model organism?

Accepted Answer

Pea plants can self-fertilize and cross-fertilize, allowing controlled breeding experiments.

Question 2

Why did the presence of clearly contrasting traits in pea plants help Mendel uncover basic inheritance patterns and disprove the blending theory of inheritance?

Accepted Answer

It allowed him to distinguish dominant and recessive traits without interpreting subtle differences.

Question 3

A child is diagnosed with a recessive disorder. Which explanation best applies to this pattern of inheritance?

Accepted Answer

Both parents are likely carriers even without symptoms, passing on two mutant alleles.

Question 4

Which statement correctly describes the conservative model of DNA replication?

Accepted Answer

The original DNA double helix is fully preserved, and a completely new helix is synthesized.

Question 5

Which of the following is NOT a protein involved in DNA replication?

Accepted Answer

origin of replication

Question 6

Eyelash length is an autosomally inherited trait. In the human population, there is one eyelash length gene. There are two possible variants of this gene – a recessive allele for long eyelashes (\u003e 1cm) and a dominant allele for short eyelashes (1 cm or less). How many different eyelash length alleles does a person with long eyelashes have in one of their somatic cells?

Accepted Answer

2

Question 7

Color blindness is a recessive X-linked trait. A normal couple has a colorblind child. Who else in this family was most likely colorblind?

Accepted Answer

the child's maternal grandfather

Question 8

If you were told that this nucleotide (see image 1) could be found in either DNA or RNA, depending on the identity of the chemical groups labeled (X) and (Y), the nitrogen-containing ring structure would have to be ________.

Accepted Answer

adenine

Question 9

Codominance occurs when:

Accepted Answer

the phenotype of a heterozygote clearly exhibits the phenotypes of both parents.

Question 10

In four-o'clock plants, red flower color is dominant to white flower color. However, heterozygous plants have a pink color. Given that the pink color of the heterozygous plants can be considered an intermediate phenotype (halfway between red and white), this deviation from Mendelian rules is due to:

Accepted Answer

Incomplete dominance

Question 11

You are performing a fruit fly cross similar to those that Morgan performed. You count the progeny and find you have 40 red-eyed males, 80 red-eyed females, and 40 white-eyed males. Assuming all genotypes from this cross should have equal survival rates, what are the genotypes of the parent flies?

Accepted Answer

XwY and X+Xw

Question 12

Why is there a need to produce Okazaki fragments on the lagging strand, but not on the leading strand?

Accepted Answer

The two parental strands of DNA are antiparallel and DNA polymerase makes DNA in the 5' to 3' direction only.

Question 13

All of the following are critical factors for DNA replication on the leading strand EXCEPT?

Accepted Answer

DNA ligase

Question 14

Based on the pedigree in image 2, Roberts Syndrome is inherited as a(n) ___________ trait.

Accepted Answer

autosomal recessive

Question 15

In the pedigree shown in image 2, what is the genotype of individual 2 in generation II?

Accepted Answer

Rr

Question 16

In the pedigree shown in image 3, what is the most likely mode of inheritance for the disease tracked in the family?

Accepted Answer

Autosomal recessive

Question 17

What is the probability that Samuel’s first child with an unaffected woman is an unaffected son? (Refer to image 3)

Accepted Answer

50%

Question 18

What is meant by the description "antiparallel" regarding the strands that make up DNA?

Accepted Answer

The 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand.

Question 19

Which of the following statements about the structure or composition of DNA is FALSE?

Accepted Answer

The amount of thymine closely approximates that of guanine within a particular organism.

Question 20

Which of the following is NOT a pyrimidine?

Accepted Answer

Guanine

BIO 201 Practice Exam Study Guidance: Genetics, DNA Structure, and Inheritance Patterns

Study Guide - Practice Questions

Study Guide - Flashcards