Origins of Life Flashcards
Last Universal Common Ancestor (LUCA)
- self replicating, metabolizing, highly complex, composed of diver macromolecules
- no single environment can fulfill all requirements
- hypothetical early cell/group of cells
- gave rise to all life on Earth
- LUCA evolve into an array of metabolisms
CHNOPS
- life evolved from gases
DNA
- stores genetic info, transcribed to RNA
RNA
- info translated into proteins
Proteins
- replication: make new DNA
- metabolism harness energy
- motion
Strecker Synthesis
Amino Acid Synthesis
- lightning discharge reactions
- promoted by acid
- requires energy input
- lightning discharge in the atmosphere
- heat from hydrothermal vents
Formose Reaction
Formation of Sugars
Fischer Tropic Type Reactions
- developed to produce fuel from inorganic precursors
- geological sources of CO2, CO, and H2
- volcanism and serpentization
Geological Perspective Bottom-Up
- environments
many prebiotic environments in which geochemistry may have allowed origins of life to occur
Biological perspective: Top-down
- cell is incredibly complex even its smallest components
catabolism
using matter to make energy
anabolism
using energy to make matter
Nucleic acids and base pairings - REPLICATION
- when a molecule makes a copy of itself
- transcription and translation
- making the proteins that power living cells
- DNA –> RNA –> protein
RNA world hypothesis
- made up of 4 different chemical building blocks
- Adenine, Guanine, Cytosine, Uracil
Photoautotrophs
light energy
- carbon from CO2
Chemoautotrophs
- energy from chemical compounds
- carbon from organic CO2
Chemoheterotrophs
- energy from chemical compounds
- carbon from organic compounds
Chemolithotrophy
organisms that generate energy by the oxidation of inorganic molecules for biosynthesis or energy conservation via aerobic or anaerobic respiration.
phylogenetic tree of life
prokaryotes vs eukaryotes
- diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor
Drake Equation
lays out factors that play a role in determining the number of communicating civilizations in our galaxy/beyond
Oxygenic Photosynthesis evolves
- cyanobacteria
Endyosymbiotic theory
- theory that eukaryotic cells formed from a symbiosis among several different prokaryotic organisms
Organics
- carbon and hydrogen in structure
Fermi’s Paradox
high probability of prior ET life
Copernican Principle
- Earth is not the center of the universe
- Sun is not center of the universe
- MODERN: there is not center to the universe
Solutions to not finding life beyond humans
(1) We are the centre of the universe and ET doesn’t exist
(2) Borrowed time: we won’t exist long enough to meet them
(3) We missed them: life on Earth hasn’t been around that long
(4) They are hiding from us
(5) We are living in a simulation - zoo hypothesis
(6) Universe is too large
Defining Intelligent Life
- self aware
- communicative
- build tools
- complex understanding
others:
- music, art, society
