This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Lecture #13: Chapter 12 CHAPTER 12: DNA: The Carrier of Genetic Information Transmission genetics: based on the extension and modification of mendelian principles: how genes get passed on from one generation to the next Molecular genetics: studying the genetic material directly Today, we do both types of genetics Questions for scientists in 30s and 40s- What are genes made of?- How do genes work? As they learned about molecules of life: they started to think about how they could correlate what they knew biochemical to genetics Requirements for the hereditary material- Precisely duplicated and transmitted to the next generation (but every so often it changes – mutatios .. then the change becomes stable)- Serves as a system of information storage and retrieval – info used to control what happens in the cell The scientists thought that it was the proteins that were the genetic material (obviously, this is wrong but they did not know about DNA yet) proteins looked like they could do anything but don’t have the most important characteristics (can’t duplicate precisely, and no information storage OR retrieval) 1928: Griffith’s Transformation Experiement- Bacteria that cause pneumonia in mice- Two strains of the bacteria: form colonies on agar o S strain – virulent (will kill you): dangerous strain of bacteria: form s mooth colonies because every cell has a polysaccharide capsule which makes the colony look smooth and glistening– can’t be phagocytized Cells were protecting from being eaten up by the polysaccharide; therefore they were completely able to multiply and kill the mouse o R strain – avirulent – form rough colonies – no polysaccharide coat – the phagocytes are...
View Full Document