Biology Unit 3

DNA

genetic information; blueprint for life; located in the nucleus

Nucleotide

Monomer or a nucleic acids (carbon, hydrogen,oxygen,nitrogen, phosphate)

Phosphate

an important acid that is in the structure of DNA

Nitrogen Bases

parts of DNA; 4 base types

Double Helix

The 3D shape of DNA

Anti-parallel

DNA has an anti-parallel structure, going from 5’ to 3’

Adenine

1 of the 4 nitrogen bases in DNA; always goes with Thymine

Thymine

1 of the 4 nitrogen bases in DNA; always goes with Adenine

Guanine

1 of the 4 nitrogen bases in DNA; goes with Cytosine

Cytosine

1 of the 4 nitrogen bases in DNA; always goes with Guanine

Histone

protein that provides structural support for chromosome

Hydrogen bonds

bonds that connect nitrogen bases together; C and G have 3 binds while A and T have 2

Leading strand

stand of DNA synthesized continuously in the direction of the replication fork

Lagging Strand

Stand of DNA synthesized discontinuously, away from replication fork creating okazaki fragments

Primase

Enzyme that synthesizes short RNA primers that are essential for DNA replication

DNA polymerase

Enzyme that creates DNA molecules by assembling Nucleotides

Helicase

Enzyme that separates double-stranded DNA into single stands

Ligase

Enzyme that glues/ bonds the okazaki fragments

Replication Bubble

a structure formed by the separation of DNA helicase

Okazaki Fragments

short sequences of DNA which are synthesized discontinuously & linked together by ligase to make the “lagging” strand

Codons

3 consecutive nucleotide that code for a specific amino acid

Anticodon

3 consecutive nucleotide that are complementary to codons

Transcription

making mRNA which carry a message from the DNA

Translation

translate mRNA into amino acids to make proteins for the cell

mRNA

messenger RNA which carries a message to the ribosome

tRNA

transfer RNA that decodes mRNA to create proteins

RNA polymerase

Enzyme responsible for copying DNA sequence (double-stranded) and turning it into RNA sequence (single-stranded)

Protein

large macromolecules necessary for the body to survive; made up of amino acids

Ribosome

cell structure that synthesizes proteins by translating genetic code of RNA into amino acids; located n the Cytoplasm

Amino Acid

Monomer of a protein; (carbon, hydrogen, oxygen,nitrogen)

Intron

DNA code removed by mRNA splicing. Introns stay INSIDE the nucleus

Extrons

DNA code kept by mRNA, exit nucleus with mRNA to ribosome

RNA

Ribonucleic acid; single stranded; travels from nucleus to ribosome for protein synthesis

Mutation

any change in a DNA sequence can be good,bad, or neutral

Point mutation

 any change in a single nucleotide

Frameshift mutation

genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read

Chromosomal Mutation

involves changes in the number or structure of chromosomes