25 Membrane-Bound Organelles

Plasma Membrane

The selective barrier which allows the sufficient passage of oxygen, nutrients, and wastes to service the entire volume of the cell at the boundary of the cell

Nucleus

Membrane based organelle whcih serves both as the repository of genetic information, and as the cell's control center. Contains a cell's chromosomes

Nuclear Envelope

Double membrane enclosing the nucleus; perforated by pores, contiguous with ER

Nucleolus

Non membranous organelle involved in production of ribosomes; a nucleus has 1 or more nucleoli.

Chromatin

Material consisting of DNA and proteins; visible as individual chromosomes in a dividing cell

Rough Endoplasmic Reticulum

A cellular organelle composed of many folds of tissues and channels; its surface is covered with ribosomes; produces proteins.

Smooth Endoplasmic Reticulum

Tube-like structure located near the cell periphery, which synthesizes lipids, phospholipids, and steroids.

Ribosome

Non membranous organelles that make proteins, free in cytoplasm or bound to rough ER nuclear envelope

Golgi Apparatus

Organelle active in synthesis, modification, sorting, and secretion of cell products

Lysosome

Digestive organelle where macromolecules are hydrolyzed

Vesicle

Sac made of membrane

Vacuole

A space or vesicle within the cytoplasm of a cell enclosed by a membrane and typically containing fluid

Mitochondrion

Organelle where cellular respiration occurs and most ATP is produced

Peroxisome

Organelle with various specialized metabolic functions; produces hydrogen peroxide

Centrosome

Region where the cells microtubules are infiltrated; in an animal cell, contains a pair of centrioles

Cytoskeleton

Reinforces cell's shape, functions in cell movement; Components made of protein

Microfilaments

Thin molecules composed principally of actin protein subunits

Intermediate Filament

Forms an elaborate network in the cytoplasm of most cells, extending from a ring surrounding the nucleus to the plasma membrane

Microtubules

A microscopic tubular structure present in numbers in the cytoplasm of cells

Flagellum

Locomotion organelle present in some animal cells; Composed of the membrane-enclosed microtubules

Cell Wall

Outer Layer that maintains cell's shape and protects cell from mechanical damage; Made from cellulose, other polysaccharides, and protein

Plasmodesma

Channels through the cell walls that connect the cytoplasm of adjacent cells

Chloroplast

Photosynthetic organelle, converts energy of sunlight to chemical energy stored in sugar molecules

Central Vacuole

Prominent organelle in older plant cells, functions include storage, breakdown of waste products, hydrolysis of macromolecules; enlargement of vacuole is a major mechanism of plant growth

Cytosol

The aqueous component of the cytoplasm of a cell, within which various organelles and particles are suspended.