Biology: Chapter 3 - Cell Structure and Function

cell theory

theory that states that all organisms are made of cells, all cells are produced by other living cells, and the cell is the most basic unit of life.

cytoplasm

jellylike substance inside cells that contains molecules and in some cells organelles.

organelle

membrane-bound structure that is specialized to perform a distinct process within a cell.

prokaryotic cell

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

eukaryotic cell

cell that has a nucleus and other membrane-bound organelles.

cytoskeleton

network of proteins, such as microtubules and microfilaments, inside a eukaryotic cell that supports and shapes the cell.

nucleus

organelle composed of a double membrane that acts as the storehouse for most of a cell's DNA.

endoplasmic reticulum

interconnected network of thin, folded membranes that produce, process, and distribute proteins.

ribosome

organelle that links amino acids together to form proteins.

golgi apparatus

stack of flat, membrane-enclosed spaces containing enzymes that process, sort, and deliver proteins.

vesicle

small organelle that contains and transports materials within the cytoplasm.

mitochondrion

bean-shaped organelle that supplies energy to the cell and has its own ribosomes and DNA.

vacuole

organelle that is used to store materials, such as water, food, or enzymes, that are needed by the cell.

lysosome

organelle that contains enzymes.

centriole

small cylinder-shaped organelle made of protein tubes arranged in a circle; aids mitosis.