{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

MCB 2007 September 10th Lecture Notes

MCB 2007 September 10th Lecture Notes - September 10th...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
September 10 th Lecture Notes: History of Life on Earth: How did the first cell develop? Earth: approximately 4.6 billion years old Life on Earth: began approximately 4 billion years ago in the ancient oceans The Miller-Urey Experiment…designed to determine if biological molecules could be generated from simple compounds in a gaseous mixture created to simulate the primitive reducing atmosphere of infant earth. The collected by- products included mostly amino acids, along with nitrogenous bases, sugars, and lipids. Where on primitive Earth did life begin? Hydrothermal vents and tidal pools seem like the best options because they provide an energy and nutrient-rich environment (think back to NASA’s definition of life and what is needed). the “primordial soup” *next step: compartmentalization to make the chemical system self-sustaining and to protect it…development of an outer lipid shell *Chemistry could now advance…cycles begin to form to maintain energy RNA and the Origins of Life: (an “RNA world” existed on Earth before the rise of modern cells) RNA fits NASA’s requirements… RNA carries information and contains a template for replication *can specify the sequence of a complementary strand, thus allowing it to replicate RNA can catalyze reactions (Ribozymes) (Altman and Cech 1989…discover RNAs can catalyze the cleavage of RNA molecules) *complementary base pairing (hydrogen bonding) can occur between base pairs of the same strand, which can give the RNA strand a unique 3-D conformation
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}