Origins of Life Where did life on earth

Origins of Life Where did life on earth begin? S

SILENTLY DO NOW In the box on your POWERNOTES, answer the following questions. 1. Define: S Theory: S Law: 2. How did life begin on Earth? (Scientific Evidence ONLY)

What are we learning today? Benchmarks ü SC. 912. L. 15. 8 – Describe the scientific explanations of the origin of life on Earth. Learning Objectives ü I will describe scientific explanations of the origin of life on Earth. ü I will identify situations or conditions contributing to the origin of life on Earth.

What is the essential question? Scientists explain that life arose from nonlife billions of years ago through theory of abiogenesis. Could life arise from nonlife today? Explain.

What is the difference between a law and a theory? S Law – a statement about the relationship between two or more things S Describes what is happening, rather than why or how S Theory – an explanation of why certain laws and facts exist S Can be tested to determine accuracy Can its anyone give us an example of a LAW? How about an example of a theory?

Primitive Earth (Early Earth) So… In Margins of your notes… Early Earth conditions: S Atmosphere contained CO 2, water, methane, and ammonia S Lacked Oxygen (O 2) q. WHERE DID LIFE BEGIN? q. HOW DID LIFE BEGIN? Without oxygen, life (as we know it today) could not be

Conditions on Earth to facilitate the origin of life: S Chemical Evolution S Introduction of Oxygen into the atmosphere S Organic Compounds such as Amino Acids

The Building Blocks of Organisms MONOMER MACROMOLECULE Amino Acid Protein Nucleotide Nucleic Acid LIFE WERE DID THE MONOMERS COME FROM? ? ?

Importance of Macromolecules Could life exist without proteins Nucleic Acids nucleic (RNA & DNA) and Earth needed the right recipe to facilitate the origin life acids? Proteins Main Point: were S Monomer: Amino. Macromolecules Acids needed in order for life to exist on S Function: Structure, Enzymes, Hormones, Storage (Virtually all. Earth cellular processes) S Monomer: Nucleotide S Function: Genetic information in living organisms

Origins of life What does origin mean? S Origin: point or place at which something begins or arises S Various theories have existed for origins of life

Key Ideas in the Origin of Life S Spontaneous Generation (Abiogenesis): Living organisms develop from non-living matter S Biogenesis: Living Click here https: //edpuzzle. com/media/59 c 11 e 9 f 3 df 50 c 5 e 8 fdb 1099 things can only arise from other living things

Failed Attempts at Explaining the Origin of Life S Oparin: Spontaneous Generation S Results: No Experiment Conducted but later experiments proved his hypothesis wrong S Redi S Pasteur S Tested S Actual hypothesis of Spontaneous Generation S Results: Disproved Spontaneous Generation success S Sided with: Biogenesis S Results: Life did not arise from non-life

EXPERIMENTS Redi What do you think this diagram is saying? Pasteur

SUCCESS STORIES S Miller-Urey Experiment (1953) S Simulated chemical conditions S Endosymbiosis Endo- Inside present on primitive earth S Synthesized: organic compounds Symbiotic: working from inorganic material S Compounds important to life Together could form on pre-biotic Earth TEACHERS: CLICK EDPUZZLE VIDEO BELOW AND SHOW NOW https: //edpuzzle. com/media/599 c 7 cc 8966 e 6240456817 a 6

SUCCESS STORIES S Endosymbiosis S Endo- Inside Symbiotic: working Together S Mitochondria and Chloroplast are result of years of evolution initiated by endocytosis (process of engulfing). Instead of digestion they learned to work together and formed eukaryotic cells S Prokaryotic cells gave rise to eukaryotic cells EVIDENCE: Both mitochondria and chloroplast have their own DNA