$$3'\text{–}UACGCA\text{–}5'$$

Question 1

Which experiment first demonstrated that genetic material could be transferred between bacteria, leading to a change in phenotype?

Accepted Answer

Griffith's experiment with Streptococcus pneumoniae

Question 2

In the Hershey-Chase experiment, which molecule was shown to carry genetic information by tracking radioactivity?

Accepted Answer

DNA, labeled with radioactive phosphorus

Question 3

Which of the following best describes the structure of a DNA nucleotide?

Accepted Answer

A phosphate group, a five-carbon sugar, and a nitrogenous base

Question 4

Which nitrogenous base is found in RNA but not in DNA?

Accepted Answer

Uracil

Question 5

What is the correct base pairing in DNA?

Accepted Answer

A pairs with T, G pairs with C

Question 6

Which scientist(s) are credited with determining the double helix structure of DNA?

Accepted Answer

Watson and Crick

Question 7

During DNA replication, what is the role of DNA polymerase?

Accepted Answer

Adds new DNA nucleotides to the growing strand

Question 8

Which enzyme connects the short fragments of DNA on the lagging strand during replication?

Accepted Answer

DNA ligase

Question 9

What is the direction of synthesis for the leading strand during DNA replication?

Accepted Answer

$$5' \rightarrow 3'$$

Question 10

Which process describes the flow of genetic information from DNA to RNA to protein?

Accepted Answer

Central dogma

Question 11

A codon is defined as:

Accepted Answer

A triplet of nucleotides in mRNA that codes for an amino acid

Question 12

What is the start codon for translation in most organisms?

Accepted Answer

$$AUG$$

Question 13

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

Accepted Answer

It is nearly universal among all organisms

Question 14

What is the function of tRNA during translation?

Accepted Answer

Brings amino acids to the ribosome and matches them to the mRNA codon

Question 15

Which mutation type is most likely to cause a frameshift?

Accepted Answer

Nucleotide insertion or deletion

Question 16

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

Accepted Answer

Nonsense mutation

Question 17

Which of the following is NOT a function of the cap and tail added to eukaryotic mRNA?

Accepted Answer

Splice introns from the mRNA

Question 18

If a DNA strand has the sequence $$5'	ext{–}ATGCGT	ext{–}3'$$, what is the complementary RNA sequence transcribed from it?

Accepted Answer

$$3'	ext{–}UACGCA	ext{–}5'$$

Question 19

Which of the following best explains why mutations can be beneficial, neutral, or harmful?

Accepted Answer

Mutations can alter protein function, sometimes improving adaptation or having no effect

Question 20

Which enzyme is responsible for unwinding the DNA helix during replication?

Accepted Answer

Helicase

Molecular Biology of the Gene: Structure, Replication, and Expression

Study Guide - Practice Questions