Question 1

Which of the following best describes the role of DNA ligase during DNA replication?

Accepted Answer

It joins Okazaki fragments together on the lagging strand.

Question 2

A scientist isolates a DNA sample and finds that 30% of the nucleotides are adenine (A). According to Chargaff's rules, what percentage of the nucleotides should be cytosine (C)?

Accepted Answer

$$C = 20\%$$

Question 3

Which of the following statements about the genetic code is correct?

Accepted Answer

The genetic code is universal, meaning all organisms use the same codons for the same amino acids.

Question 4

Which enzyme is responsible for synthesizing mRNA from a DNA template during transcription?

Accepted Answer

RNA polymerase

Question 5

A mutation changes a codon from UAU (tyrosine) to UAA (stop codon). What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 6

Which of the following best explains why DNA migrates toward the positive electrode during gel electrophoresis?

Accepted Answer

DNA is negatively charged due to its phosphate backbone.

Question 7

Which of the following is a function of restriction enzymes in biotechnology?

Accepted Answer

They cut DNA at specific sequences, creating sticky or blunt ends.

Question 8

A researcher wants to amplify a specific DNA sequence from a small sample. Which technique should they use?

Accepted Answer

Polymerase Chain Reaction (PCR)

Question 9

Which of the following best describes a transgenic organism?

Accepted Answer

An organism that contains DNA from another species.

Question 10

Which of the following is a real-world application of producing human growth hormone (HGH) in bacteria?

Accepted Answer

Producing human-identical hormone for medical treatments.

Question 11

Which of the following statements about Okazaki fragments is correct?

Accepted Answer

They are joined together by DNA ligase on the lagging strand.

Question 12

Which of the following best describes the function of tRNA during translation?

Accepted Answer

It brings amino acids to the ribosome and matches them to the mRNA codon.

Question 13

Which of the following is a difference between DNA and RNA?

Accepted Answer

DNA is usually double-stranded, while RNA is usually single-stranded.

Question 14

Which of the following best explains why the genetic code is described as 'redundant'?

Accepted Answer

Multiple codons can code for the same amino acid.

Question 15

A patient is found to have a point mutation in a gene. Which of the following best describes a point mutation?

Accepted Answer

A change in a single nucleotide pair in DNA.

Question 16

Which of the following is a function of feedback regulation in gene expression?

Accepted Answer

It ensures that the end product of a pathway regulates the pathway itself.

Question 17

Which of the following best describes the role of an operator in an operon?

Accepted Answer

It is a segment of DNA that acts as an on/off switch for transcription.

Question 18

Which of the following is a correct statement about heterochromatin and euchromatin?

Accepted Answer

Euchromatin is loosely packed and active in transcription.

Question 19

Which of the following best describes the function of PCR (Polymerase Chain Reaction) in biotechnology?

Accepted Answer

To make millions of copies of a target DNA sequence.

Question 20

Which of the following is a characteristic of induced pluripotent stem cells (iPS cells)?

Accepted Answer

They are adult cells reprogrammed back into stem-like cells.

Study Guide: The Molecular Basis of Inheritance, Gene Expression, and Biotechnology

Study Guide - Practice Questions

Study Guide - Flashcards