People Flashcards
1
Q
What are Mendel’s contributions?
A
- Law of segregation
- Law of independent Assortment
2
Q
What contributions did Watson and Crick make?
A
- structure of DNA–>said it was a double-helix with sugar phosphate backbones on the outsides and nucleotide bases arrayed in complementary pairs toward the center
- used Chargaff’s rule to formulate the
hypothesis that nucleotides are arranged as complementary base pairs (A with T and C with G)
3
Q
What did chargaff discover?
A
for most organisms the percentage of
adenine and thymine are equal, and the percentage of guanine and cytosine are equal
4
Q
What were Mendel’s 5 critical experimental innovations?
A
- controlled crosses between plants
- used pure-breeding strains in experimental crosses
- used single traits with dichotomous phenotypes(each trait had 2 forms)
- quantification of results: was able to detect ratios that are the foundation of his laws of heredity
- replicate, reciprocal, and test-crosses
5
Q
beadle and tatum?
A
one gene-one enzyme
6
Q
davis?
A
used U-tube to show that genetic transfer/production of prototrophic cells required physical contact
