Have three parts:

sugar (ribose)

phosphate

nitrogen base

The nitrogen base has two parts:

purines: adenine and guanine

pyrimidines: cytosine and uracil (only in RNA)

sequences of amino acids that correspond to genes;

a proteins primary structure;

the only class of RNA that carries the protein-building codes.

transcribed genes that specify proteins;

the first step in protein synthesis;

a sequence of ncleotide bases is exposed in an unwound region of a DNA strand;

protein coding base sequences that are interrupted by nncoding sequences (introns);

(all introns are snipped off before the transcript reaches the cytoplasm)

bse triplets in mRNA strands;

happens when tRNA and mRNA strands bind together;

the freedom in codon-anticodon pairing at a base;

intereactions between tRNA and mRNA take place at ribosomes. 

Only mRNA carries DNA's protein-building instructions from the nucleus into the cytoplasm;

tRNA delivers amino acids to ribosomes. Their anticodons base-pair with codons in the order specified by mRNA.

a polypeptide chain is synthesized while the mRNA passes between the two ribosomal subunits;

i.e. athread being moved through the eye of a

 needle;

RNA polymerse adds free complementary nucleotides to DNA strand;

RNA polymerse (tRNA) binds to DNA at promoter region;

DNA polymerse unravel DNA dbl helix;

RNA polymer reaches stop sequence and stops transcription;

process of RNA makind protein;  occurs in the cytoplasm

methionine is the 1st amino acid in protein process in humans (20 total);

Mutation

fall into to categories:

insertion mutation - addition of nitrogen base

deletion mutation- removal of a nitrogen base

jump around in the genome;

segements of DNA (or sopies) that move spontaneously to a new location in a chromosome or even to a different chromosome.

form of radiation with enough energy to eject electrons from atoms;

may cause mutations in DNA if exposed in large doses;