Download Important Cell Vocabulary Definitions

Cell: The smallest unit (part) of an organism
Tissue: A group of cells that work together to
perform a specific job in the body
Organ: A group of tissues that work together to
perform a specific job in the body
Organism: Anything that can live on its own
Unicellular: An organism that is made up of only
one cell
Multicellular: An organism that is made up of
multiple cells
Population: A group of organisms that are of the
same kind and that live in the same area
Community: Two or more populations living in the
same area
Ecosystem: The community and all of the nonliving
things that affect it, such as water, soil, rocks,
temperature, and light
Cell Membrane: A layer that covers a cell’s surface
and acts as a barrier
Cell Wall: A structure that surrounds the cell
membrane of some cells and provides strength and
support to the cell membrane
Nucleus: The membrane-covered organelle found
in eukaryotic cells that contain the cell’s DNA and
serves as the control center for the cell
Ribosome: A small organelle in cells where proteins
are made from amino acids
Endoplasmic Reticulum: A membrane-covered cell
organelle that produces lipids, breaks down drugs
and other substances, and packages proteins for
delivery out of the cell
Mitochondria: Cell organelles surrounded by two
membranes that break down food molecules to
make ATP (energy)
Chloroplast: An organelle found in plant and algae
cells where photosynthesis occurs
Golgi Complex: The cell organelle that modifies,
packages, and transports materials out of the cell
Vesicle: A membrane-covered compartment in a
eukaryotic cell that forms when part of the cell
membrane surrounds an object and pinches off
Vacuole: a large membrane-covered structure
found in plant cells that serves as a storage
container for water and other liquids
Lysosomes: Special vesicles in animal cells that
contain enzymes, and are used to digest food
particles, wastes, cell parts, and foreign invaders