32 terms

science vocab 9 and 10!

quiz on this Friday, October 23!!
substance prepared from killed or weakened pathogens and introdeced into a body to produce immiunity
referring to the deadliness of a disease-causing agent
the transfer of genetic material from one organism to another; first observed by Griffith
a virus that infects bacteria
double helix
spiral-staircase structure characteristic of the DNA molecule
subunit of nucleic acids; consisting of a nitrogenous base, a sugar, and a phosphate group
five-carbon that is a component od DNA nucleotides
base-pairing rules
the rule stating that in DNA adenine on the strand always pairs with thymine on the opposite strand and guanine on one strand always pairs with a cytosine on the opposite strand
characterisic of nucleic acids in which the sequence of bases on one strand determines the sequence of bases on the other
DNA replication
the process of making a copy of DNA
DNA helicase
enzyme that breaks the hydrogen bonds between bases during DNA replication
replication fork
a Y-shaped point that results when a double helix of DNA separates so that it can be copied
DNA polymerase
enzyme that catalyzes the replication of DNA by adding complementary nucleotides
ribonucleic acid (RNA)
a type of nucleic acid involved in protein synthesis
nitrogen-containing base of RNA, complementary to adenine when RNA base pairs with DNA
stage of protein synthesis in which the information in DNA for making a protein is transferred to an RNA molecule
gene expression
two-stage processing of information encoded in DNA to produce protein
RNA polymerase
enzyme that adds and links complementary RNA nucleotides during transcription
messenger RNA
RNA copy of a gene used as a blueprint for the making of a protein during translation
a three-nucleotide sequence in DNA or mRNA that encodes an amino acid or signifies a stop signal
genetic code
sequence of nucleotides that specifies the amino acid sequence of a protein
transfer RNA
RNA moleule that temporarily carries a specific amino acid to a ribosome during translation
a three-nucleotide sequence on tRNA that recognizes a complementary codon on mRNA
ribosomal RNA
type of RNA molecule that plays a structural role in ribosomes
region of DNA that contols RNA polymerase's acess to a set of genes with related functions
segment of DNA that controls gene regulation in a set of genes with related functions in prokaryoyes
lac operon
gene system with a promoter; an operator gene, and three structural genes that control lactose metabolism
protein that binds to the operator in an operon to switch off transcription
segment of mRNA transcribed from eukaryotic DNA but removed before translation of mRNA into a protein
sequence of nucleotides on a gene that gets transcribed and translated
point mutation
mutation in which one or just a few of nucleotides in a gene are exchanged
stage of gene expression in which the gene information in mRNA is used to make protein