DNA

Question 1

The Code of Life

Answer 1

• inherited traits give us sae features to parents
• genes are carried on chromosomes in DNA form
• inherrited and respobible for pheotyphic chartestertics

Question 2

Friedrich Miescher

Answer 2

• 1869
• he isolated a compound found in the nucleus of cell
• named compound nuclein
• many scientists did studys after to see if it was heridetery material

Question 3

nucleiod and heridty

Answer 3

nuclein was discovered in the 1920s, but it took decades still to determine it was responsible for heredity

Question 4

Joachim Hammerling

Answer 4

• In the 1930
• single-celled algae would regrow if the nucleus was still present
• detrmined nucleus must contain the genetic material

Question 5

Alfred Hershey and Martha Chase

Answer 5

• proved hammerlings hyponthsis in 1952

Question 6

how did hershey and chase prove hammerlings hypthosis

Answer 6

• showing that viruses only need to inject their DNA into a cell to take over their organelle to produce more virus
• proved that DNA was the hereditary material

Question 7

Chemical Composition of DNA

Answer 7

A pentose sugar (5 carbon cyclical sugar)
A phosphate group with a negative charge
A nitrogenous base
components together are called a nucleotide

Question 8

Phoebus Levene

Answer 8

• 1920s
• discovered DNA had 3 main components

Question 9

4 possible nitrogenous bases

Answer 9

• make up the nucleotides of DNA
  Adenine (A)
  Guanine (G)
  Thymine (T)
  Cytosine (C)

Question 10

relationship between the nitrogenous bases

Answer 10

The amount of Adenine =
The amount of Thymine
The amount of Guanine =
The amount of Cytosine

crucial clue that helped determine the structure of DNA

Question 11

Rosalind Franklin

Answer 11

• scientists did not know struture to DNA
• work with Maurice Wilkins
• In 1951
• studied DNA using X-ray crystallography
• discovered that the DNA molecules must have a helix, or corkscrew, shape

Question 12

James Watson and Francis Crick

Answer 12

• In 1953
• met with Wilkins and stole franklins idea
• everyone knew the shap eof DNA< double helix

Question 13

main events of DNA

Answer 13

• DNA is made of a pentose sugar, a phosphate group and nitrogenous bases (Levene, 1920s)
• The proportion of A to T and C to G is equal (Chargaff, 1940)
• DNA has the shape of a helix (Franklin and Wilkins, 1951)

Question 14

Erwin Chargaff

Answer 14

• In 1940
• discovered a key relationship about the nitrogenous bases

Question 15

events in order

Answer 15

• 1869, Friedrich Miescher
• 1920s, Phoebus Levene
• 1930s, Joachim Hammerling
• 1940, Erwin Chargaff
• 1951, Rosalind Franklin and Wilkins
• 1952, Alfred Hershey and Martha Chase
• 1953, James Watson and Francis Crick