EVOLUTION ORIGIN OF LIFE THE BIG BANG EVOLUTION

EVOLUTION ORIGIN OF LIFE

THE BIG BANG

EVOLUTION: THE BIG BANG • 10 -20 billion years ago all matter, energy, space and time came into existence • The universe expanded very rapidly and began to cool down • Matter began to condense and new atoms/particles formed

EVOLUTION: THE ACCRETION THEORY • 4. 6 billion years ago dust and light elements began to collide and condense together in a process called accretion • The larger the clump the more surface area it has, the faster it gathers more particles • When large enough they develop their own gravitational field and eventually become the planets we know today • CONGRATULATIONS!

EVOLUTION: EARTH ATMOSPHERE • 4. 6 BYA - Surface was mostly molten and atmosphere was formed mainly from hydrogen sulfide, methane and 200 times as much carbon dioxide • 4 to 2. 5 BYA – Cyanobacteria flourished in oceans and started producing oxygen

EVOLUTION: EARTH ATMOSPHERE • 700 to 550 MYA – Oxygen levels reached about 4% of atmosphere causing an explosion of oxygen using lifeforms (Cambrian explosion) • 430 MYA – Small plants and invertebrates appear on land • 416 to 397 MYA – Plants and animals evolve and first four footed animals begin to form

ORIGIN OF LIFE • Evolution – Change in the genetic makeup of a population of organisms over time • Abiogenesis - the process of life arising from non-living matter • Miller-Urey experiment produced organic compounds from simulated early Earth atmosphere • https: //www. youtube. com/wat ch? v=iah. BQol. XQH 8

ORIGIN OF LIFE TIMELINE

PROKARYOTES AND EUKARYOTE • The first cells on Earth were heterotrophic prokaryotes (bacteria) • Heterotroph – organism that can not make its own food and eats in order to survive • Early prokaryotes consumed organic matter from pre-historic sea • Some mutated into autotrophs (produce own food)

PROKARYOTES AND EUKARYOTES • Early autotrophs manufactured own food in two ways: • 1. Photosynthesis – producing food from light energy a. Stromatolites – single celled cyanobacteria; clumped into rock like structures • 2. Chemosynthesis – energy from inorganic materials (deep sea hydrothermal vents)

PROKARYOTES AND EUKARYOTES • Prokaryotes, such as mitochondria and chloroplast, began to live inside larger prokaryotes • Resulted in the formation of more complex cells that we now call eukaryotic cells • Theory of Endosymbiosis – origin of eukaryotic cells from mutualistic relationship between prokaryotes

PROKARYOTES AND EUKARYOTES • Evidence supporting Theory of Endosymbiosis: • 1. Mitochondria and chloroplast have their own DNA • 2. DNA resembles the DNA of prokaryotes more than DNA of eukaryotes • 3. Mitochondria and chloroplast have their own double membrane

PROKARYOTES AND EUKARYOTES