Nucleotide

Anticodon

A sequence of three bases of a tRNA molecule that pairs with the complementary three-nucleotide codon of an mRNA molecule during protein synthesis.

DNA polymerase

An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides to the existing chain.

Messenger RNA

RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell

Ribosomal RNA

The most abundant type of RNA, which together with proteins, forms the structure of ribosomes. Ribosomes coordinate the sequential coupling of tRNA molecules to mRNA codons.

Chromatin

granular material visible within the nucleus; consists of DNA tightly coiled around proteins

Nucleotide

monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base

Base-pairing

principle that bonds in DNA can form only between adenine and thymine and betwen guanine and cytosine

Gene

sequence of DNA that codes for a protein and thus determines a trait

Translation

the act of changing in form or shape or appearance

Transcription

the act of making a record (especially an audio record)

Replication

the repetition of an experiment in order to test the validity of its conclusion

Codon

three-nucleotide sequence on messenger RNA that codes for a single amino acid

RNA polymerase

transcription enzyme that links RNA nucleotides together

Double helix

two strands of nucleotides wound about each other; structure of DNA

Transfer RNA

type of RNA molecule that transfers amino acids to ribosomes during protein synthesis