Cell Biology Vocabulary

Cells

The basic structural, functional, and biological unit of all living organisms.

Cell Theory

A fundamental theory in biology that states that all living organisms are composed of cells, and that all cells arise from pre-existing cells.

Microscopes

Instruments used to see objects that are too small for the naked eye, allowing for the observation of cells and microorganisms.

Eukaryote

An organism whose cells contain a nucleus and other organelles enclosed within membranes.

Prokaryote

A unicellular organism that lacks a membrane-bound nucleus and organelles, typically smaller and simpler than eukaryotic cells.

Cell Membrane

A biological membrane that separates and protects the interior of all cells from the outside environment.

Nucleus

The membrane-bound organelle in eukaryotic cells that contains the genetic material (DNA) and controls cellular activities.

Cytoplasm

The jelly-like substance within a cell, excluding the nucleus, where organelles are suspended and metabolic processes occur.

Ribosome

A cellular structure that synthesizes proteins by translating messenger RNA.

Endoplasmic Reticulum

An organelle that forms an interconnected network of membranes involved in protein and lipid synthesis; comes in two forms: rough and smooth.

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

Vacuole

A membrane-bound organelle in cells that stores nutrients, waste products, and helps maintain turgor pressure in plant cells.

Lysosome

An organelle that contains digestive enzymes to break down waste materials and cellular debris.

Chloroplast

An organelle found in plant cells and some algae that conducts photosynthesis, converting light energy into chemical energy.

Mitochondria

Organelles known as the powerhouses of the cell, responsible for producing energy (ATP) through cellular respiration.

Cell Wall

A rigid outer layer that provides structural support and protection to plant cells, fungi, and some bacteria.

Hydrophobic

Describing molecules that do not interact well with water; typically nonpolar substances.

Hydrophilic

Describing molecules that interact well with water; typically polar or charged substances.