DNA
The 4 nitrogenous bases
What is Adenine (A), Thymine (T), Cytosine (C), Guanine (G)
What sugar is found in RNA?
Ribose
What is the region on an enzyme where the substrate binds?
Answer: The active site.
What is a mutation?
Answer: A change in the DNA sequence.
During what phase of the cell cycle does DNA replication occur?
Answer: S phase.
The types of bonds that hold base pairs together in the DNA double helix.
What are hydrogen bonds?
What is the role of mRNA in protein synthesis?
Answer: It carries the genetic code from DNA to the ribosome.
What happens to an enzyme if it is exposed to extremely high temperatures?
Answer: It becomes denatured and loses its function.
What is the difference between a point mutation and a frameshift mutation?
Answer: A point mutation changes a single nucleotide, while a frameshift mutation adds or deletes a nucleotide, shifting the reading frame.
List the phases of mitosis in the correct order.
Answer: Prophase, Metaphase, Anaphase, Telophase.
What does it mean that DNA replication is "semi-conservative"
Each new DNA molecule consists of one new original strand and one new newly synthesized strand.
Where in the cell does transcription occur?
Answer: In the nucleus.
What is the “induced fit” model of enzyme function?
Answer: It describes how the enzyme changes shape slightly to fit the substrate more snugly.
Are all mutations harmful? Explain.
Answer: No, some mutations are neutral, some are beneficial (e.g., evolution), and some are harmful.
What happens during metaphase of mitosis?
Answer: Chromosomes line up in the middle of the cell.
What is the name of the enzyme that unzips the DNA strands during replication?
What are the three types of RNA, and what are their functions?
• mRNA: Carries the genetic code.
• tRNA: Transfers amino acids to the ribosome.
• rRNA: Forms part of the ribosome.
What is the difference between a substrate and a product in an enzymatic reaction?
Answer: The substrate is the molecule the enzyme acts on, and the product is the molecule(s) formed after the reaction.
What type of mutation occurs when a single nucleotide is swapped for another?
Answer: Substitution (point mutation).
What is cytokinesis, and how is it different from mitosis?
Answer: Cytokinesis is the division of the cytoplasm, while mitosis is the division of the nucleus.
Describe the roles of DNA polymerase and ligase in DNA replication
DNA polymerase adds complementary nucleotides to the template strand, while ligase seals the Okazaki fragments on the lagging strand.
Translate this mRNA sequence into a protein: AUG-GCU-UAC-GGG-UAA.
Answer: Methionine - Alanine - Tyrosine - Glycine (STOP).
How do enzymes speed up chemical reactions?
Answer: They lower the activation energy needed for the reaction to occur.
Why are frameshift mutations more harmful than point mutations?
Answer: Frameshift mutations alter the entire reading frame, potentially changing all amino acids in the sequence after the mutation.
What is the result of uncontrolled cell division?
Answer: Cancer.