History of life and phylogenetic (copy)

Origin of Life

The process by which life arose on Earth, facilitated by early conditions and biochemical processes.

Early Earth Conditions

Conditions on Earth that provided a suitable environment for the emergence of life, including essential inorganic molecules.

Essential Inorganic Molecules

Molecules like water (H2O), methane (CH4), ammonia (NH3), and hydrogen cyanide (HCN) that were necessary for the origin of life.

Four Main Stages of Cell Formation

Stages include: 1) Abiotic synthesis of organic molecules, 2) Formation of macromolecules, 3) Formation of protocells, 4) Emergence of self-replicating molecules.

Stage 1: Abiotic Synthesis

The combination of inorganic molecules to form small organic molecules such as amino acids.

Stage 2: Formation of Macromolecules

Small organic molecules linked to form larger molecules like proteins and nucleic acids.

Stage 3: Formation of Protocells

Macromolecules packaged into droplets called protocells, which maintained distinct internal chemistry.

Stage 4: Emergence of Self-replicating Molecules

Self-replicating molecules that facilitated inheritance and evolution.

Miller-Urey Experiment

An experiment that demonstrated the formation of organic compounds under prebiotic conditions.

Ribozyme

RNA molecules capable of catalyzing chemical reactions, including their own replication.

Protocells

Simple membrane-bound structures that could perform basic life functions and contributed to the development of cellular life.

Prokaryotes

The first life forms on Earth, thriving in anaerobic environments.

Oxygen Revolution

A significant increase in Earth's atmospheric oxygen leading to the evolution of more complex life forms.

Endosymbiotic Theory

The theory explaining the origin of eukaryotic cells from symbiotic relationships between prokaryotic cells.

Phylogenetic Trees

Diagrams that illustrate the evolutionary history and relationships among species based on shared ancestors.

Monophyletic Group

A group that includes an ancestor and all its descendants.

Shared Ancestral Traits

Traits that are shared by all members of a clade, indicative of common ancestry.

Derived Traits

Traits not present in the common ancestor of a group, used to distinguish different lineages.

Parsimony Principle

The principle that favors the simplest explanation, requiring the fewest changes in constructing phylogenetic trees.

Three Domains of Life

Classification consisting of Bacteria, Archaea (prokaryotes), and Eukarya (eukaryotes) based on cellular structures.