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animal cellclick to hear

Smallest living structure and constituent unit of all animals, including human beings; its size and shape vary according to function.
animal cell microtubule cilium microfilament peroxisome cell membrane chromatin nucleus ribosome endoplasmic reticulum mitochondrion cytoplasm vacuole lysosome nuclear envelope nucleolus centriole Golgi apparatus

microtubule click to hear

Cylindrical structure supporting the cell and allowing organelles and substances inside the cell to move about.

cilium click to hear

Filament-like extension of the cytoplasmic membrane allowing the cell and certain substances on its surface to move about.

microfilament click to hear

Rod-shaped structure supporting the cell and giving it its shape.

peroxisome click to hear

Organelle containing enzymes that neutralize the cell’s toxic substances.

cell membrane click to hear

The cell’s flexible outer casing; it separates the cell from the surrounding environment and works as a filter to control the entry and exit of certain substances.

chromatin click to hear

Mass of very fine filaments of DNA, the genetic material of the cell; it is compressed into chromosomes during cell division.

nucleus click to hear

Organelle containing a cell’s genes and controlling its activities.

ribosome click to hear

Organelle, free or attached to the endoplasmic reticulum, producing proteins essential to the constitution and functioning of living beings.

endoplasmic reticulum click to hear

Organelle formed of walls to which the ribosomes are attached.

mitochondrion click to hear

Ovoid organelle that produces the energy necessary for cell activity.

cytoplasm click to hear

Clear gelatinous substance surrounding the various cellular structures.

vacuole click to hear

Spherical cavity containing water, waste and various substances required by the cell.

lysosome click to hear

Small spheroid organ containing enzymes that break down food, spent cell components and other harmful substances that have been absorbed.

nuclear envelope click to hear

Envelope formed of two layers surrounding the nucleus and pierced with small holes, which allow exchanges between the cytoplasm and the nucleus.

nucleolus click to hear

Small spherical body located inside the nucleus, within which the ribosomes, or protein-synthesizing structures, are produced.

centriole click to hear

Structure consisting of small rods that play a major role in cell division. Each cell usually contains two.

Golgi apparatus click to hear

Organelle composed of a series of pockets that receive proteins produced by the ribosomes and either transport them outside the cell or to other organelles.