Cell Structure & Function

Cell TheoryAll living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

Definition of CellA cell is the smallest unit that is capable of performing life functions.

Examples of CellsAmoeba ProteusPlant StemRed Blood CellNerve CellBacteria

Typical Animal Cell

Typical Plant Cell

Cell PartsSurrounding the Cell

Cell MembraneOuter membrane of cell that controls movement in and out of the cellDouble layer

Cell WallMost commonly found in plant cells & bacteriaSupports & protects cells

Inside the Cell

Nucleus Directs cell activitiesSeparated from cytoplasm by nuclear membraneContains genetic material - DNA

Nuclear MembraneSurrounds nucleusMade of two layersOpenings allow material to enter and leave nucleus

ChromosomesIn nucleusMade of DNAContain instructions for traits & characteristics

NucleolusInside nucleusContains RNA to build proteins

CytoplasmGel-like mixtureSurrounded by cell membraneContains hereditary material

Endoplasmic ReticulumMoves materials around in cellSmooth type: lacks ribosomesRough type (pictured): ribosomes embedded in surface

RibosomesEach cell contains thousandsMake proteinsFound on ribosomes & floating throughout the cell

MitochondriaProduces energy through chemical reactions breaking down fats & carbohydratesControls level of water and other materials in cellRecycles and decomposes proteins, fats, and carbohydrates

Golgi BodiesProtein 'packaging plant'Move materials within the cellMove materials out of the cell

LysosomeDigestive 'plant' for proteins, fats, and carbohydratesTransports undigested material to cell membrane for removalCell breaks down if lysosome explodes

VacuolesMembrane-bound sacs for storage, digestion, and waste removalContains water solutionHelp plants maintain shape

ChloroplastUsually found in plant cellsContains green chlorophyllWhere photosynthesis takes place