Levels of Organization in Living Systems

Life: Levels of Organization

Subatomic Particles

• Protons, Neutrons, Electrons

Atom

• The smallest particle of an element.
• Example: Depiction of a molecule with chemical formula "CH₂OH" and structural representations showing arrangements of carbon, hydrogen, and oxygen atoms.

Molecule

• Two or more atoms linked together by covalent bonds.

Organelle

• Part of a cell with a specific function.
• Example: nucleus.

Cell

• The basic unit of living matter.

Tissue

• A group of similar cells that together perform a specific function.

Organ

• Consisting of several tissues that together perform a specific task.

Organ System

• Multiple organs that together perform a vital body function.

Organism

• (Multicellular): a living thing.

Population

• Group of individuals of the same species that live in the same area at the same time.
• Referenced with a food web example including: Fox, Rabbit, Owl, Hawk, Snake, Mouse, Frog, Grasshopper, Grasses and Bird.

Community

• Different organisms living and interacting in the same area.

Ecosystem

• A community of living things plus all the nonliving features of the environment that support them.

Biosphere

• The sum of all the Earth's ecosystems.

Emergent Properties

• “The whole is greater than the sum of its parts”
• A property that emerges from the whole that is not present in any of the parts
  • Mechanical Example: Bicycle; The property of transportation does not emerge from a box of bicycle parts. But! If those parts are put correctly together into a bicycle…the property of transportation emerges.
  • This property is not present in any of the particular parts, but rather, is a property that emerges from the whole of the parts put together.
  • Biological example: Heart; The functional property of the heart is pumping blood. The parts that make up the heart (atoms, molecules, tissues) cannot pump blood. The action of pumping blood emerges from the organizational structure of the parts together.