chromosomes
discrete unit of the genome carrying many genes
structural gene
a gene that codes for any RNA or polypeptide product other than a
regulator
transforming principal
DNA that is taken up by a bacterium and whose expression then
changes the properties of the recipient cell
transfection
in eukaryotic cells, the acquisition of new genetic markers by
incorporation of added DNA
nucleoside
consists of purine or pyrimidine base linked to the 1' carbon of a
pentose sugar
,nucleotide
consists of a nuclease linked to a phosphate group on either the 5' or
3' carbon of the (deoxy)ribose
polynucleotide
chain that is joined by a phosphate group between the 3' carbon of
one sugar and 5' carbon of the next sugar
supercoiling
the coiling of a closed duplex DNA in space so that it crosses over its
own axis
complementary
base pairs that match up in the pairing reactions in double helical
nucleic acids
major groove
,wide
minor groove
narrow
overwound
B-form DNA that has more than 10.5 base pairs per turn of the helix
underwound
B-form DNA that has fewer than 10.5 base pairs per turn of the helix
semiconservative replication
DNA replication accomplished by separation of the strands of a
perennial duplex, each strand then acting as a template for synthesis
of a complementary strand
denaturation
, in DNA this involves the separation of the two strands due to breaking
of hydrogen bonds between bases
renaturation
the reallocation of denatured complementary single strands of DNA
double helix
replication fork
the point at which the parental strands are seperated
DNA polymerases
the enzymes that synthesize DNA
endonucleases
cleaves a bond within a nucleic acid
exonucleases
removes bases one at a time