Cells & Their Functions

Des: Outer layer of the cell; composed mainly of lipids and proteins. Fx: Encloses the cell; regulates what enters and exits, participates in activities such as growth, reproduction, and interactions between cells.

Des: Short extensions of the cell membrane Fx: Contains the chromosomes, the hereditary units that direct all cellular activities.

Des: Large, dark-staining organelle near the center of the cell, composed of DNA and proteins Fx: Contains chromosomes, the hereditary units that direct all cellular activities.

Des: Small body in the nucleus; composed of RNA, DNA, and protein. Fx: Makes ribosomes

Des: Colloidal suspension that fills the cell from the nuclear membrane to the plasma membrane Fx: Site of many cellular activities; consists of cytosol and organelles.

Des: The fluid portion of cytoplasm Fx: Surrounds the organelles.

Des: Network of membranes within the cytoplasm. Rough ER has ribosomes attached to it. Smooth ER does not. Fx: Rough ER sorts proteins and forms them into more complex compounds; smooth ER is involved with lipid synthesis.

Des: Small bodies free in the cytoplasm or attached to the ER; composed of RNA and proteins. Fx: Manufactures proteins.

Des: Large organelles with folded membranes inside. Fx: Convert energy from nutrients to ATP.

Des: Layers of membranes Fx: Makes compounds containing proteins; sorts and prepares these compounds for transport to other parts of the cell or out of the cell.

Des: Small sacs of digestive enzymes Fx: Digest substances within the cell

Des: Membrane-enclosed organelles containing enzymes. Fx: Break down harmful substances.

Des: Small membrane-bound sacs in the cytoplasm. Fx: Store materials and move materials into or out of the cell in bulk.

Des: Rod-shaped bodies (usually two) near the nucleus. Fx: Help separate the chromosomes during cell division.

Des: Structures that extend from the cell. Fx: Move the cell or the fluids around the cell.