This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Protobionts-Aggregates of abiotically produced molecules surrounded by a membrane-Liposomes can form when lipids or other organic molecules are added to water The Chicken or the Egg Now-DNA->RNA->Protein-Need proteins to synthesize more DNA Then-Earliest cells used RNA to store info-Ribozymes to catalyze reactions Ribozymes-Found to catalyze many different reactions including-Self splicing-Making complementary copies of short-stretches of RNA Possible sequence leading to first prokaryotes Concept 25.2: The fossil record documents the history of life Fossils Document the History of life-Sedimentary strata reveal the relative ages of fossils -Fossils near surface more recent-Deeper fossils more ancient-Fossil records shows great changes in organisms through time Dating of Fossils-Order of fossils in rock strata tells us the sequence in which they were laid down-This provides relative ages, not absolute dates...
View Full Document
This note was uploaded on 03/27/2010 for the course BIOL 1202 taught by Professor Gregg during the Spring '08 term at LSU.
- Spring '08