Dudes

Question 1

Beadle and Tatum

Answer 1

1941

Des covered that genes are responsible for the synthesization for enzymes

Stated that hereditary diseases are unborn errors of metabolism, and DNA controls metabolism in body

Neurospora - haploid organism contains simple sugars, inorganic salts, converts into amino acids for vitamins and growth

Question 2

Griffith

Answer 2

Experimented with strains of pneumococcus bacteria, causing pneumonia

DNA transforms and mutates

Mice were injected with S strain, die within days from pneumonia , R strain did not

Heated S strain to kill bacteria -> did not give pneumonia

Heated S strain with live R strain caused pneumonia

Question 3

Avery, McCarthy, MacLeod

Answer 3

S stand and R strand

Came up with transforming principle

DNA is the transforming substance or “controller of cell” and changing the cell

Question 4

Hershey

Answer 4

1952

Discovered bacteria have sex

Conjunction = genes are exchanged through mating channel

Used virus and bacteria, put sulphur and phosphorus into bacteria, we’re seeing if protein or DNA function as genetic material

Question 5

Chargaff

Answer 5

1949

Isolated DNA in different organisms

Found that thymine and adenine were almost identical = chargaffs rule (base pairs)

Bases occur in definite ratios in double stranded DNA

Question 6

Watson and Crick

Answer 6

1952

Published the first accurate model of DNA molecule, discovered DNA forms double helix and half of that helix forms a template (mirror helix)

Question 7

Meischer

Answer 7

1869
Discovered substance in cell (nuclein) that was high in phosphorus and acidic

Studied white blood cells - major component of pus from bandages

Added weak alkaline to cells, saw cells lysed and nuclei precipitate out of alkaline solution(salt)

Never discovered biological function of nuclein

Question 8

Meselston and Stahl

Answer 8

1958

They showed that new DNA is made by copying from the old

Experimented using hydrogen isotopes and density gradient configuration