Cell Organelle Chart

ORGANELLE

In bacteria?

In plant?

In animal?

STRUCTURE & FUNCTION

Cell membrane
(Plasma membrane)

Yes

Yes

Yes

Boundary between intracellular & extracellular environments. Regulates entry/exit of substances.

Cell wall

Yes, usually

Yes

No

Rigid structure providing support for cell.

Cytoplasm

Yes

Yes

Yes

Jelly-like substance filling intracellular space contains dissolved substances.

Cyto-skeleton

No

Yes

Yes

Network of fine tubes and threads. Provides internal structural support.

Centrioles

Rarely

No, but aster is similar.

Yes

Paired rods, which help organize microtubules during mitosis.

Nucleus

No

Yes

Yes

Membrane-bound structure containing cells' genetic information (DNA) and support molecules.

Nucleolus

No

Yes

Yes

Small structure within nucleus. Site of production of ribosomal RNA.

Nuclear Membrane

No

Yes

Yes

Boundary between nucleus and cytoplasm. Regulates passage of materials between the two.

Flagella, pili or cilia

Sometimes flagella or pili

Rarely, but some specialized cells may.

Only present in some specialized cells.

Structures used to enable movement of cells or sometimes to propel substances across outer surface of the cell. Predominantly protein in composition.

Mitochondria

No

Yes

Yes

Membrane bound organelles. Folded membranes within contain enzymes for aerobic respiration. (A little DNA in here too.)

Chloroplasts

No

Only in photosynthetic cells

No

Membrane bound organelles. Folded membranes within contain chlorophyll and enzymes for photosynthesis. (A little DNA in here too.)

Vacuole

No

Yes, often large

Unusual, and small if present.

Membrane bound area filled with water and assorted solutes. Role in maintenance of water balance of the cell.

Ribosomes

Yes

Yes

Yes

Small organelles at which protein synthesis occurs. May be free floating or membrane-bound.

Endoplasmic reticulum
(ER) -smooth

No

Yes

Yes

Network of flattened membranes forming tunnels. Enzymes assisting synthesis of some lipids and final processing of proteins found here.

Endoplasmic reticulum
(ER) -rough

No

Yes

Yes

Similar to smooth ER, but with ribosomes embedded in membrane. Proteins to be exported from cell produced here.

Golgi apparatus

(aka Golgi Body)

No

Yes

Yes

Stacks of saucer shaped membranes where export proteins are modified and stored prior to entering secretory vesicles for exocytosis.

Lysosomes

No

Yes

Yes

Membrane bound structure-containing enzymes, which break down toxic or unwanted molecules.

Plastids

No

Yes

No

Membrane bound structures with varied functions. Leucoplasts - starch storage. Chromoplasts - colored pigments within (eg flower petals).

Vesicles

No

Rare

Yes

Packages for storage (eg fat droplets) or temporary transport associated with endocytosis/exocytosis.

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