Look at these charts.

 

LEVEL	DEFINITION	EXAMPLE
Biosphere	The portion of the Earth and atmosphere where life exists	The air, water, and terrestrial areas where life can exist; biomes plus atmosphere
Ecosystem	The living things in an area, along with their environment	The seashore including all the animals, plants, algae as well as the wind, minerals/rocks, water and weather
Community	All of the populations that live in a defined area	All the animals, plants, fungi and bacteria that live together in a forest
Population	A group of individuals in the same species within a defined area	Squirrels in your neighborhood, algae growing in a test tube
Organism	A living thing (may be unicellular- see cell)	Blue Whale, Mushroom, Pine Tree
Organ System	A group of organs that work together to perform a function	Circulatory System, Nervous System
Organ	A group of different tissues that work together to perform a function	Heart, Brain, Kidney, Skin
Tissue	A group of cells that perform a similar function	Muscle tissue, Blood
Cells	The basic unit of structure and function in living things	Muscle cell, E.coli bacterium
Organelle	One of many cell structures that have a specialized function	Nucleus, ribosome, mitochondria, chloroplasts
Macromolecule	A large, complex molecule; essential molecule for life’s processes/structures	Carbohydrates, Proteins
Molecule	Different atoms that are chemically bonded together	Water, Carbon Dioxide
Atom	Basic unit of matter; building blocks of molecules	Carbon, Hydrogen, or Oxygen atoms are common in living things

 

(charts source)