Honors Biology Vocab Terms

molecular biology

the study of heredity of the molecular level

nucleotides

the monomers of a nucleic acid that link together to form DNA or RNA

double helix

The structure of DNA, determined by Watson, Crick and Franklin

x-ray crystallography

A scientific procedure developed by Franklin that was used to determine the shape of DNA

semi conservative

when dna copies itself, each new strand is half old (parental) and half new (daughter strand)

parental strand

original strand of dna

helicase

an enzyme that untwists the double helix of dna at the replication forks and makes the dna into two single strands

primase

an enzyme that synthesizes primers, which are necessary for initiating dna replication

dna polymerase

an enzyme that adds the nucleotides to the daughter strand

ligase

The enzyme that glues all the fragments together at the end of DNA replication

phenotype

(physical traits) comes from the action proteins

genotype

(genetic makeup) sequence of nucleotide bases in the dna

transcription

the transfer of genetic information from dna into an rna molecule, happens in the nucleus

translation

the transfer of information from rna into a protein, happens at the ribosomes

codon

triplet of bases & codes for amino acid

amino acid

the fundamental molecule that serves as the building block for proteins

replication

when a cell reproduces a complete copy of dna has to go into each new cell

initiation

The first step of transcription where RNA polymerase attaches to the promoter

elongation

rna polymearase continues to add bases and rna strand grows longer

termination

rna polymearse reaches a sequence of dna called the terminator

promoter

nucleotide sequence that acts at the start transcirbing signals

terminator

a specific dna sequence that signals the end of transcription, the process of creating RNA from DNA

mRNA

messenger rna; carries instructions from dna in the nucleus to the ribosome

tRNA

transfer rna; carries amino acids to the ribosome

rRNA

ribosomal rna; makes up part of the ribosome or protein builders of the cell