transformation
process in which one strain of bacteria changes into another one
bacteriophage
virus that infects bacteria
histone
protein that DNA wraps around in eukaryotic chromosomes
replication
process in which DNA makes a copy of itself
DNA polymerase
the principal enzyme involved in DNA replication
promoter
signal in DNA that indicates to an enzyme where to bind to make RNA
introns
sections of RNA molecules that are removed before a eukaryotic gene becomes functional
codon
three nucleotides taht specify a single amino acid to be added to a polypeptide
mutation
a change in the genetic material
polyploidy
condition of having extra sets of chromosomes
operon
a group of genes that operate together
differentiation
process in which cells become specialized in structure and function
base printing
principal that bonds in DNA can form only between adenine and thymine and between guanine and cytosine
chromatin
granular material visible within the nucleus; consists of DNA tightly coiled around proteins
genes
coded DNA instructions
messenger RNA (mRNA)
RNA molecule that carries copies of instuctions for the assembly of amino acids into proteins from DNA to the rest of the cell
ribosomal RNA (rRNA)
type of RNA that makes up the major part of ribosomes
transfer RNA (tRNA)
type of RNA molecule that transfers amino acids to ribosomes during protein synthesis
RNA polymerase
enzyme similar to DNA polymerase that binds to DNA and spearates the DNA strands during transcription
exons
expressed sequence of NDA; codes for a protein
translation
decoding of a mRNA message into a polypeptide chain
anticodon
group of three bases on a tRNA molecule that are complementary to an mRNA codon
mutation
change in a DNA sequence that affects genetic information
point mutation
gene mutation involving changes in one or a few nucleotides
frameshift mutation
mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide
operator
region of chrmosome in an operon to which the repressor binds when the operon is "turned off
hox genes
series of genes that controls the differentiation of cells and tissues in an embryo