Dec 10, 2025 · What is a cell? A cell is a mass of cytoplasm that is bound externally by a cell membrane. Usually microscopic in size, cells are the smallest structural units of living matter and …

Jun 14, 2025 · Explore the structure, types, and functions of cells in this student-friendly guide to cell biology and cell theory.

Cell theory, developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells, that cells are the fundamental unit of structure and …

Apr 9, 2025 · Explore the structures and functions of 24 cell organelles with detailed diagrams, enhancing your understanding of cellular components in biology.

Jul 23, 2025 · Every cell is made up of cytoplasm that is enclosed in a membrane and includes many small molecules of nutrients and metabolites as well as many macromolecules including proteins, …

Explore the structures and functions of major eukaryotic cell organelles. Understand how the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, chloroplasts, and ribosomes …

A cell consists of three parts: the cell membrane, the nucleus, and, between the two, the cytoplasm. Within the cytoplasm lie intricate arrangements of fine fibers and hundreds or even thousands of …

Intracellular fluid is collectively the cytosol and the fluid inside the organelles and the cell nucleus. Membranes are the gateways to the cell. The cell membrane (or plasma membrane) is the selective …

Cells fall into one of two broad categories: prokaryotic and eukaryotic. The predominantly single-celled organisms of the domains Bacteria and Archaea are classified as prokaryotes (pro- = before; -karyon …

Aug 1, 2025 · Delve into the complex internal architecture of cells. Explore how their specialized structures work together to perform life’s vital functions.