DNA structure & nucleotides
These two nitrogen bases always pair together: adenine with this base.
What is thymine?
These three‑letter “words” in mRNA each code for one amino acid.
What are codons?
This codon signals the ribosome to begin building a protein.
What is the start codon (AUG)?
This term describes any change in the DNA sequence, whether small or large.
What is a mutation?
This lab method separates DNA fragments by size as they move through a gel when electricity is applied.
What is gel electrophoresis?
This sugar is found in DNA nucleotides and helps form the backbone of the molecule.
What is deoxyribose?
This molecule carries the instructions from DNA to the ribosome so proteins can be built.
What is mRNA?
This part of the tRNA pairs with the codon on the mRNA during protein synthesis.
What is the anticodon?
This type of mutation replaces one nitrogen base with another, sometimes changing a single amino acid.
What is a substitution?
This technique copies a specific piece of DNA over and over using heating and cooling cycles.
What is PCR?
These are the building blocks of DNA, each made of a sugar, a phosphate, and a nitrogen base.
What are nucleotides?
This molecule brings amino acids to the ribosome, matching them to the correct codon.
What is tRNA?
This molecule brings amino acids to the ribosome and matches them to the correct codon.
What is tRNA?
These two types of mutations—where a base is added or removed—can shift the reading frame of the genetic code.
What are insertion and deletion mutations?
This process changes an organism’s DNA by adding, removing, or altering genetic material.
What is genetic engineering?
These bonds hold the nitrogen bases together in the center of the DNA molecule, like rungs on a ladder.
What are hydrogen bonds?
This codon signals the start of protein synthesis and codes for the amino acid methionine.
What is AUG?
This type of RNA carries the genetic message from DNA to the ribosome.
What is mRNA?
This kind of mutation does not change the amino acid made, even though the DNA sequence is altered.
What is a silent mutation?
This type of DNA molecule, often found in bacteria, is used to carry new genes into cells during genetic engineering.
What is a plasmid?
This shape describes the structure of DNA, with two strands twisted around each other.
What is a double helix?
These three codons tell the ribosome to stop building the protein.
What are stop codons?
These three‑letter sequences on mRNA each code for one amino acid.
What are codons?
This environmental factor, such as UV light or radiation, can increase the chance of DNA mutations.
What is a mutagen?
This tool acts like tiny molecular scissors, cutting DNA at specific sequences.
What is a restriction enzyme?