Unit 6 APBIO Vocab

gel electrophoresis

Procedure used to separate and analyze DNA fragments by placing a mixture of DNA fragments at one end of a porous gel and applying an electrical voltage to the gel

lac operon

a gene system whose operator gene and three structural genes control lactose metabolism in E. coli

carcinogen

A cancer-causing substance

codon

A specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid

point mutation

gene mutation in which a single base pair in DNA has been changed

Regulator (operon)

gene that codes for repressor

structural genes (operon)

genes that code for proteins

ribozyme

a type of RNA that can act as an enzyme

vector

an organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another. Species of mosquito, for example, serve as vectors for the deadly disease Malaria.

replication fork

A Y-shaped region on a replicating DNA molecule where new strands are growing.

mutagen

A chemical or physical agent that interacts with DNA and causes a mutation.

DNA ligase

A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain.

Promotor

A region of DNA with a specific sequence that tells RNA polymerase where to begin transcription.

plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

DNA helicase

An enzyme that unwinds the DNA double helix during DNA replication

genetically modified organism

An organism whose genetic material has been altered through some genetic engineering technology or technique.

exons

Coding segments of eukaryotic DNA.

recombinant DNA

DNA produced by combining DNA from different sources

DNA replication

DNA unzips into two parts and splits with the cell. In its new side each side of the DNA strand attack to matching nucleotides to create 2 exact copies; important in puberty and other times of growth as it is the reproducing of your cells.

RNA polymerase

Enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription

restriction enzyme

Enzyme that cuts DNA at a specific sequence of nucleotides

heterochromatin

Eukaryotic chromatin that remains highly compacted during interphase and is generally not transcribed.

semiconservative replication

Method of DNA replication in which parental strands separate, act as templates, and produce molecules of DNA with one parental DNA strand and one new DNA strand

introns

Noncoding segments of nucleic acid that lie between coding sequences.

transgenic organism

Organisms that contain functional recombinant DNA from a different organism

translation

Process by which mRNA is decoded and a protein is produced

Single-stranded binding proteins

Proteins that act as scaffolding, holding two DNA strands apart during replication

gene therapy

The insertion of working copies of a gene into the cells of a person with a genetic disorder in an attempt to correct the disorder

repressor (operon)

When end product is present in excess, operon is turned off

genetic code

collection of codons of mRNA, each of which directs the incorporation of a particular amino acid into a protein during protein synthesis

operon

group of genes operating together

anticodon

group of three bases on a tRNA molecule that are complementary to an mRNA codon

Euchtomatin

lesser chromatin compaction; heavy gene expression; condensation variable during cell cycle; lightly stained regions

mRNA transcript

mRNA molecule formed during transcription that has a sequence of bases complementary to a gene.

mRNA

messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome

frameshift mutation

mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide

rRNA

ribosomal RNA; type of RNA that makes up part of the ribosome

genomics

study of whole genomes, including genes and their functions

DNA primase

synthesizes short RNA primers

operator (operon)

the binding site for the repressor, which turns off the Lac operon

Transcription

the organic process whereby the DNA sequence in a gene is copied into mRNA

tRNA

transfer RNA; type of RNA that carries amino acids to the ribosome

trp operon

tryptophan binds to the repressor protein and enables it to repress gene transcription.

promoter (operon)

where RNA polymerase binds