Organelle

File:Biological cell.png

Schematic of typical animal cell, showing subcellular components. Organelles: (1) nucleolus (2) nucleus (3) ribosome (4) vesicle,(5) rough endoplasmic reticulum (ER), (6) Golgi apparatus, (7) Cytoskeleton, (8) smooth ER, (9) mitochondria, (10) vacuole, (11) cytoplasm, (12) lysosome, (13) centrioles

In cell biology, an organelle is one of several structures with specialized functions, suspended in the cytoplasm of a eukaryotic cell. Organelles were historically identified through the use of some form of microscopy and were also identified through the use of cell fractionation.

A few large organelles probably originated from endosymbiont bacteria:

• chloroplast
• mitochondrion

Other organelles include:

• acrosome
• centriole
• endoplasmic reticulum
• golgi apparatus
• lysosome
• myofibril
• plastids
• nucleus
• peroxisome
• ribosome
• vacuole
• vesicle
• melanosome
• cilium/flagellum

Other related structures:

• cytosol
• endomembrane system
• nucleosome
• microtubule
• cell membrane

See also

• Cell
• Endosymbiotic theory.