lecture14 - The History of Earth and Life Lecture 14 Origin...

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

View Full Document Right Arrow Icon
The History of Earth and Life Lecture 14 Origin and Early Evolution of Life Origin and Early Evolution of Life - Overview What is life? Life processes and building blocks of life Theories about the origin of life Biochemical theory How did life originate? Where did life originate? When did life originate? The earliest record of life The simplest life forms Life in the Archean times Life 1. Self-replicating (reproduction) 2. Self-regulating 3. Carbon-based systems Why carbon? Carbon forms four covalent bonds Carbon can form large molecules of varied shape (e.g., chain-like structures) Other elements that can form four bonds form ionic bonds Carbon is a common element Organic Polymers - Building Blocks of Life Most organic molecules are polymers of simple monomers There are 4 major groups of polymers: 1. Nucleic acids — phosphates, sugars, nitrogenous bases 2. Proteins — amino acids 3. Carbohydrates — Carbon and water 4. Lipids — glycerol and fatty acids Life Processes Metabolism The chemistry of life functions (controlled by enzymes) Energy from breakdown of organic compounds Nutrition Acquisition of energy and materials for life Reproduction Replication of genetic information
Background image of page 1

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

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

This note was uploaded on 03/24/2008 for the course GEOS 1014 taught by Professor Sxiao during the Spring '08 term at Virginia Tech.

Page1 / 3

lecture14 - The History of Earth and Life Lecture 14 Origin...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online