Biology | Introduction to Cells

Prokaryote

a cell that does not include a nucleus or other membrane-bound organelles

Eukaryote

a cell that contains a nucleus and other organelles, each surrounded by a thin membrane (can be single-celled or multicellular)

Organelles

a cell structure that performs a specific function

Cell membrane

an outer layer that provides protection for a cell as well as transports nutrients into a cell and toxic substances outside of it

Nuclear membrane

a barrier that separates the nucleus from the cytoplasm

nucleolus

a spherical structure in the cell’s nucleus that produces and assembles a cell’s ribosomes

nucleus

holds genetic inforation and controls and reulates the activities of a cell

DNA

contains what is needed for an organism to develop, survive, and reproduce

Chloroplasts

produces energy through photosynthesis and oxygen-release processes to sustain plant growth

Cytoplasm

a jelly-like substance that holds the organelles in place and protects them from damage

endoplasmic reticulum

can either be smooth or rough and produces proteins for the rest of the cell to function

ribsomes

can be free or attached to the ER and execute biological protein synthesis in all living cells

lysosome

breaks down molecules in cells for digestion and removal of waste

mitochondria

releases chemical energy stored in food molecules in order to generate usable energy in the cell

vesicle

can move molecules, secrete substances, digest materials, or regulate the pressure in the cell

golgi apparatus

helps recieve proteins and lipid molecules espeically proteins that need to be exported from the cell

large permanent vacuole

provides structural support as well as storage, waste disposal, protection, and growth

temporary vacuole

temporarily stores materials or to transport substances

cell wall

provides strength and protection against osmotic stress, mostly in plant cells

cytoskeleton

helps cells maintain their shape and internal organization