Biology DNA/RNA, Protein Synthesis, & Genetic Engineering

Monomers of DNA

nucleotides

3 main parts of a nucleotide

a phosphate group, a sugar, and a nitrogenous base

Double helix

term used to describe the physical structure of DNA

4 nitrogenous bases of DNA

adenine, cytosine, guanine, and thymine

Difference between DNA and RNA nitrogenous bases

RNA contains uracil instead of thymine

Base pairs in DNA

AT GC — Adenine paired with thymine and cytosine paired with guanine.

Difference between DNA and RNA base pair

DNA pairs adenine with thymine instead of uracil.

Purines

Have 2 carbon/nitrogen rings and are made of Adenine and Guanine

Pyrimidines

have 1 carbon/nitrogen ring and are made of Thymine and Cytosine

Holds DNA together

Hydrogen Bonds

Transcription

DNA → RNA — copying of genetic information from code of DNA to code of mRNA

Translation

RNA → protein — process in which instructions in mRNA are used to assemble polypeptides to make a protein 

Genetic Code

the sequence of nitrogen bases

Codon

series of 3 mRNA nucleotides which code for a specific amino acid

Anti-codon

a loop on clover leaf shaped tRNA which pairs with its complementary mRNA codon

Polypeptide Chain

a chain of amino acids made from the pairing of the codon and the anti-codon (Translation)

tRNA

Transfer RNA — serves as a link between the mRNA and the chain of amino acids

Complimentary base pairing

the way nitrogen bases pair together

Helicase

Unzips DNA by breaking hydrogen bonds between base pairs to start replication

Primase

Creates small RNA primers on the unzipped DNA to mark the starting point of new DNA

Polymerase

Creates DNA molecules by assembling nucleotides on the unzipped DNA

Exonuclease

Removes RNA primers

Ligase

Seals DNA fragments into a single strand

Semi-conservative replication

When each new strand of DNA has one original (conserved) parent strand

Prokaryotic DNA

Has no nucleus and instead has a single DNA strand in the cytoplasm

Eurkaryotic DNA

Enclosed in a nucleus and has 8-46 chromosomes

Chromosomes are made of

A protein and a single molecule of deoxyribonucleic acid (DNA)

Substitution Mutation

A type of point mutation where a nucleotide is replaced by another

Deletion Mutatiton

A type of frame shift mutation where a base is deleted and the rest are shifted down

Insertion Mutation

A type of frame shift mutation where a base is inserted and the rest are shifted away

Point mutation

a mutation where only one base pair is affected