Read the descriptions of the parts of a cell and in which type of cells each can be found.
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Cell Membrane
A selectively permeable lipid bilayer that separates the interior of the cell from the outside environment. Regulates substances moving into and out of the cell. (Found in eukaryotes and prokaryotes.)

Cell Wall
A tougher layer around a cell that provides structural support and protection. (pro & some euk)

Centriole
Cylindrical organelles found in pairs, each made of nine microtubule triplets. Help organize the mitotic spindle during cell division. (euk)

Chloroplast
Found only in plant cells, these green organelles contain thylakoids, which are where photosynthesis takes place. (euk)

Cilia
Small hair-like projections on the outsides of cells. May serve motility or sensory functions, depending on the cell. (euk & pro)

Cytosol
A gelatin-like substance inside the cell that cushions organelles. (euk & pro)

Flagella
Longer, whip-like projections on the outsides of cells. Used for motility in bacteria, and for motility and sensing in eukaryotic cells. (euk & pro)

Golgi Apparatus
A stack of smooth membrane sacks called cisternae. Packages proteins for delivery to other parts of the cell or for secretion outside the cell. (euk)

Lysosome
A small vesicle containing acidic enzymes to digest waste within the cell. (euk)

Mitochondria
Double-layered organelles with the inner membranes forming folded structures called cistae. Responsible for ATP synthesis. Often called the powerhouse of the cell. (euk)

Nuclear Envelope The outer membrane of the nucleus that is contiguous with the rough ER. Acts as a barrier to keep molecules in the cytosol from moving into the nucleus. (euk)

Nucleoid
A region found only in prokaryotic cells that contains the genetic material of the cell. Unlike the nucleus in eukaryotic cells, the nucleoid region of prokaryotic cells has no membrane surrounding it. (pro)

Nucleolus
A structure made of proteins and nucleic acids found within the nucleus. Produces ribosomes. (euk)

Nucleus
A dense, spherical organelle surrounded by the nuclear envelope. It contains the cell's genetic material. (euk)

Peroxisome
A small vesicle containing oxidative enzymes that break down toxic materials in the cell. Similar to lysosomes, but contains oxidative enzymes that lysosomes do not. Often responsible for digesting long-chain fatty acids. (euk)

Plasmid
A circular piece of DNA separate from chromosomes that can replicate independently of the rest of the cell. (pro)

Ribosome
Each ribosome is made up of a large and small subunit. They are responsible for protein synthesis. Thousands can be found within one cell, either attached to rough ER or floating freely in the cytosol. (euk & pro)

Rough Endoplasmic Reticulum (ER)
A network of membrane sacs extending out from the nuclear envelope into the cytosol. Rough ER is studded with ribosomes that synthesize proteins. It shuttles the completed proteins elsewhere in the cell. (euk)

Smooth Endoplasmic Reticulum (ER)
A network of membrane sacs extending out from the nuclear envelope into the cytosol. Responsible for lipid and steroid synthesis and metabolism of carbohydrates. (euk)

Vacuole
A membrane-bound sac containing mostly water and some small molecules. Functions vary depending on cell type. In plants they are often used for turgid support. (euk & pro)