B5.1.8 History of Genetics

Question 1

What did Mendel do?

Answer 1

1866 Crossed tall pea plant w dwarf pea plant
-all offspring were tall
Crossed offspring w each other
- 25% dwarf, 75% tall
Explained by genetic cross diagram
Discovered dominant and recessive inherited factors

Question 2

1869 Nuclein discovery

Answer 2

Fredrick Meischer discovered acidic substance in nucleus of cell (DNA)

Question 3

1944 Genes transferred from one generation to next

Answer 3

Oswald Avery discovered transferred DNA between bacteria, passing ability to cause disease from one strain to another and to offspring = genes made up of DNA

Question 4

1950 DNA base pairs discovered

Answer 4

Erwin Chargaff found although different organisms contain different amounts of DNA, all contain same amounts of adenine and thymine, as well as cytosine and guanine

Question 5

1952 DNA crystals photographed

Answer 5

Maurice Wilkins and Rosalind Franklin imaged DNA crystals using x-rays

Question 6

1953 Double-helix structure of DNA identified

Answer 6

James Watson and Francis Crick published description of DNA as a double helix-two spirals held together by complimentary bases

Question 7

1953-2000 Advances in genetics

Answer 7

Scientists discovered individual genes that code for genetically inherited diseases
Genetic engineering developed, altered organism’s characteristics by adding genetic material

Question 8

2003 Human Genome Project Completed

Answer 8

20 y/o project completed as scientists working across globe identified and sequenced complete set of genes in human body

Question 9

2003+ research

Answer 9

Currently attempting to do gene therapy - replace faulty/mutated gene with normal copies of gene to cure genetic diseases