Hierarchy of Biological Organization Levels of Organization

Life is organized Life is highly organized into structural levels. Each level builds on the levels below it.

Atoms Chemical building blocks of mater Organized into biological molecules

Organelles Molecules are organized into small structures called organelles Organelles are the components of cells

Cells Subunits of organisms. Cell is the smallest unit capable of all life functions Some organisms are only 1 cell. Ex. Amoeba Types of Blood cells AMOEBA

Tissues Similar cells are grouped into tissues. Nervous tissue, epithelial tissue, muscle tissue, connective tissue

Organs Specific arrangement of different tissue form organs Heart, lung, kidney Organs form organ systems like the nervous system

Organ Systems When organs work together they form systems. Ex. Circulatory system

Organism All the other parts form an organism that is part of a larger population. Can continue to communities, ecosystems, and biosphere.

Beyond Individual Organism There are tiers beyond the individual. Population: A group of species Community: Groups of populations of species Ecosystem: Community interactions that include non-living features.

Emergent Properties Each step upward in the hierarchy of order, different properties emerge that were not present at the simpler level of organization. Ex: Properties of proteins have attributes that were not exhibited by any of it’s component atoms.

Emergent Properties Cont. Emergent properties are integral to the formation of life as non-living things are organized into what we perceive life to be. This is what “life” resists a simple one-sentence definition.