Question 1

Which of the following best describes a transposable element (TE) in the genome?

Accepted Answer

A selfish genetic element capable of moving within the genome

Question 2

Class I transposable elements (retrotransposons) are most similar to which of the following?

Accepted Answer

Viruses, because they use reverse transcription to replicate

Question 3

Which feature distinguishes retrotransposons from retroviruses?

Accepted Answer

Retrotransposons lack the env gene required for viral particle formation

Question 4

What is the primary mechanism by which Class II DNA transposons move within the genome?

Accepted Answer

Cut and paste using a transposase enzyme

Question 5

TE integration into the genome often results in which of the following sequence features?

Accepted Answer

Flanking direct repeats at the insertion site

Question 6

A TE insertion in the middle of an exon is most likely to:

Accepted Answer

Disrupt the reading frame and potentially cause disease

Question 7

Barbara McClintock was awarded the Nobel Prize in 1983 for her discovery of:

Accepted Answer

Mobile genetic elements (transposable elements)

Question 8

Approximately what percentage of the human genome is composed of transposable elements?

Accepted Answer

$$\sim 45\%$$

Question 9

Which of the following is a consequence of TE insertions in the human genome?

Accepted Answer

They can cause genetic diseases by disrupting gene function

Question 10

Which process is used to exponentially amplify a specific genomic region for sequencing?

Accepted Answer

Polymerase Chain Reaction (PCR)

Question 11

During PCR, what is the purpose of heating the DNA to 95°C?

Accepted Answer

To denature the DNA and separate the strands

Question 12

Which equation best describes the exponential amplification of DNA during PCR after $$n$$ cycles, starting with $$N_0$$ molecules?

Accepted Answer

$$N = N_0$ 	imes 2^n$$

Question 13

Whole genome shotgun sequencing involves which of the following steps?

Accepted Answer

Fragmenting the genome and sequencing each piece multiple times

Question 14

Why do repetitive sequences such as transposable elements complicate genome assembly?

Accepted Answer

They create identical sequence regions that cannot be uniquely assigned to a location

Question 15

Metagenomics is particularly useful for studying:

Accepted Answer

Microbes that cannot be cultured in the laboratory

Question 16

Which of the following statements about gene density is correct?

Accepted Answer

Bacteria and archaea have the highest gene density

Question 17

Which of the following is NOT a step in genome annotation?

Accepted Answer

Whole genome shotgun sequencing

Question 18

A researcher finds a TE insertion in the promoter region of a gene. What is the most likely effect?

Accepted Answer

Altered gene expression

Question 19

Which of the following best explains how incomplete DNA transposons can still move within the genome?

Accepted Answer

If transposase is provided elsewhere in the genome, non-autonomous elements can be mobilized

Question 20

Which of the following is a real-world example of a disease caused by TE insertion?

Accepted Answer

Breast cancer associated with BRCA2 Alu insertion

Chapter 16 a

Study Guide - Practice Questions