LIFESCI 3 Lecture Notes - Lecture 3: Frederick Griffith, Streptococcus Pneumoniae, Nucleophile
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Ls 3 - lecture #3 - dna experiments & proteins. Frederi(cid:272)k griffith studied strepto(cid:272)o(cid:272)(cid:272)us p(cid:374)eu(cid:373)o(cid:374)ia (cid:271)a(cid:272)teria to e(cid:454)a(cid:373)i(cid:374)e (cid:862)rough(cid:863) a(cid:374)d (cid:448)irule(cid:374)t (cid:894)har(cid:373)ful(cid:895) (cid:862)s(cid:373)ooth(cid:863) strai(cid:374)s. Observed that some rough bacteria were transformed into virulent smooth strain when exposed to dead virulent smooth strain bacteria. For this course, less emphasis is placed on names and dates, focus on main concepts. Os(cid:449)ald a(cid:448)er(cid:455)"s e(cid:454)peri(cid:373)e(cid:374)ts (cid:272)o(cid:374)(cid:272)luded i(cid:374) 1944 that bacterial transformations are caused by dna. Significant because during this period of time, proteins were thought to be responsible because dna was seen as too simple a substance. Labeled the dna and proteins of the t2 virus to examine which was transmitted when the virus injected its information into bacteria. It was known that whatever substance was transmitted by the virus to the bacteria caused the bacteria to transform. Why were dual experiments performed instead of one (i. e. could not otherwise determine the source of the radiation. Clicker question: the following are commonly used radioisotopes.
