Prokaryotic cells
dna in cytoplasm
eukaryotic cells
dna in nucleus
chromatin
granular material visible within the nucleus; consists of DNA tightly coiled around proteins
histone
protein molecule around which DNA is tightly coiled in chromation
replication
copying process by which a cell duplicates its DNA
DNA polymerase
enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule
5' to 3'
way the DNA is replicated
phosphate
attached to 5'
hydroxyl group
attached to 3'
anitparallel
parallel but moving in opposite directions
A
attaches to T
G
attaches to C
A,G
purines
C,T
pyrimides
purines
double ringed
pyrimides
single ringed
gene
sequence of DNA that codes for a protein and thus determines a trait
messenger RNA (mRNA)
RNA molecule that carries copies of instructions for assembly of amino acids into proteins from DNA to rest of cell
ribosomal RNA (rRNA)
type of RNA that makes up a major part of ribosomes
transfer RNA (tRNA)
type of RNA molecule that transfers amino acids to ribosomes during protein synthesis
transciption
process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in RNA
RNA polymerase
enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription
promoters
region of DNA that indicates to an enzyme where to bind to make RNA
exons
expressed sequence of DNA; code for proteins
intron
sequence of DNA that is not involved in coding for a protein
codon
3 nucleotide sequence on messenger RNA that codes for a single amino acid
translation
decoding of mRNA message into a polypeptide chain
anticodom
group of 3 bases on a tRNA molecule that are complementary mRNA codon
helicase
enzyme whose function is unpackages an organism's genes
primase
enzyme that makes primer
Okazaki fragments
short, newly synthesized DNA fragments that are formed on the lagging strand during DNA replication
leading strand
dna strand that is synthesized continuously during replicaiton
lagging strand
dna strand that is synthesis discontinuously
ligase
enzyme that catalyzes the binding of two molecules