1869, used fish sperm, found that the fluid inside is nuclein, has acidic pH

used pneumococcus bacteria

-S Type pneumococcus- deadly, encapsulated in protein coat

- R Type pneumococcus- harmless, nonencapsulated

Injects S, mouse dies

Injects R, mouse lives

Injects S microwaved, mouse lives

Mix of microwaved S and regular R cells, mouse dies

Bacteria transfomation!!!!!

1994

-identified transforming material in Griffith experiment as DNA

-transformation= when bacteria take up foreign DNA

1953

-used bacteriophage, mixed radioactive (sulfur + phospherous) phages with bacteria, which infect bacteria

-agitated in blender to seperate phages outside the bacteria from the cells/ their content

-centrifuge mixture...

-saw that only DNA from viruses was injected into E.Coli, not the coat

-therefore DNA is genetic material

deoxyribonucleic acid

-phosphate group/5-C sugar/Nitrogen base (adenine, thymine, guanine, cytosine)

-Hydrogen bonds between complementary base pairs from opposite strands

1953

-used x-ray studies of DNA (Rosalin Franklin)

-used crystals to figure out that DNA has double helix shape

Won nobel prize in 1958, Rosalin died same year

1. Hydrogen bond between complimentary base pairs break

2. Two Strands unzip like halves of a zipper

3. Free nucleotides' Nitrogen bases are attracted to complementary bases on exposed strand.

4. Free nucleotides and exposed bases form complete complementary strand of DNA

5. Two identical helixes are formed

THIS IS SEMI CONSERVATIVE REPLICATION, both original strands stay intact

ribonucleic acid

-amino acid= subunit

-5-C sugar = ribose

- N-bases, not thymine-->URACIL

-single strand

-->DNA

--> Transcription (copying of gene)

--> RNA

--> Translation

--> Protein

-copying of genetic message to make polypeptide from DNA to molecule of mRNA

mRNA: messenger RNA, carries code from DNA to ribosome

CODON= GROUP OF 3 BASES ON mRNA THAT SPECIFY AND AMINO ACID

occurs in nucleus

RNA polymerase

-the transfer of informationg from a nucleotide sequence on mRNA into an amino acid sequence

-to make polypeptide/protein

-Translates nucleotide language into amino acid language

-in cytoplasm

-tRNA= transfer RNA, 80 nucleotides long, carries particular amino acids to mRNA @ ribosome, picks up AA in cyptoplasm, is clover shaped, and very specific

-Anti codon- sequence of 3 bases complementary to mRNA-->45 types

-once mutation occurs, it is copied through all offspring replications of DNA, but most mutations are recdessive, most do not help organism

-causes: random, environmental factors (UV rays, x rays, mutagens), preservatives/ food additives

Types of Mutations

1. Chromosomal mutations: rearrangement, loss, or duplication of whole sections of DNA

2. Point mutations: changes in 1 or a few nucleotides in DNA

-Base substitution: mutation in which single complementary base pair accidently changes into a wrong one.

Outcomes: Silent Mutation, no effect on protien structure/function because sequence code is the same

Missense Mutation:affects either both protein STRUCTURE + FUNCTION or just structure, new sequence codes for a different but similar amino acid

Nonsense Mutation: Shortened protein created if new sequence codes for a stop codon

-Frameshift Mutation: complementary base pairs are accidentally added or deleted from a DNA molecule, makes codons misread, result=abnormal protein