The smallest structural and functional unit of an organism.

Examples: nerve cells and brain cells

is made up of similar cells that combine to perform a function.
group of similar cells performing a job or function
Examples: nerve tissue and brain tissue

Similar tissues combine to make ?
Tissues organized into brain, heart, lungs, stomach, etc.
Examples: brain, skin, stomach

The result of several organs working together to perform a function.

Examples: digestive system, nervous system and cardiovascular system

Organ systems work together to make an ?
Individual living thing (person, dog, plant, etc.)
Example: human

group of one kind of organism (species) in an area that can interbreed & make fertile offspring --- (cardinals at the bird feeder)

Several populations of organisms in an area --- (animals in the zoo)

All the living (biotic) and nonliving (abiotic) parts of an environment --- (Tropical rain forest, grassland, etc.)

Large areas of the world with similar climates and organisms

All the living and nonliving things on Earth