TWO CATAGORIES FOR DISTINGUISHING CELL TYPE

Prokaryotic Eukaryotic

PROKAYOTE• Smaller and simpler• Have cell membrane and

cytoplasm• No nuclei• Some DNA within

cytoplasm• All bacteria are

prokaryotes• They grow, reproduce,

respond to change• Some move

EUKARYOTE• Vary in shape, some large • Have cell membrane and

cytoplasm• Have nuclei and many

other organelles• Some single-celled beings• Many multi-celled beings• All plants, animals, fungi,

and many microorganisms are eukaryotes

Cell MembraneLocation•Outer boundary of animal and protist cells. Outer edge of cytoplasm.Function•Regulates what enters and exits the cell•Supports cell structures and provides strong barrier between cell and surroundings.Construction•Lipid bilayer, also containing proteins and carbohydrates

Cell WallLocationOuter most boundary in plant, bacteria and fungi cells

Function• Provides support and protection for the cell•Helps maintain cell shape

NucleusLocation•In all cells but bacteria cells•Often most prominent structure in center of cell

Function•Controls cell processes•Stores hereditary information of DNA•Codes for protein synthesis (making of proteins most important role of cell)

Nuclear EnvelopeLocation•Surrounds nucleusFunction•Double membrane layer that contains pores which allow material to move into and out of the nucleus•Steady stream of RNA and other info-carrying molecules to the rest of the cell

Nucleolus

Location•Dark spherical mass inside the nucleus

Function•Assembly of ribosomes begin here

CytoplasmLocation•Material inside the cell membrane but not including the nucleus•Contains many structures called organelles•Some cells may contain cytoskeleton

FunctionEstablishes living condition to supply and transport materials for cell activities

CytoskeletonLocation•Extending from nucleus to cell membrane in some cells

Description•Made up of protein filaments called microtubules and microfilaments

Function•Helps cell maintain shape and involved in many forms of cell movement

Endoplasmic Reticulum (E.R.)Location•Extend from nuclear envelope to cell membraneDescriptionRough E.R. – contain ribosomesSmooth E.R. – do not contain ribosomesFunction•Transport materials•Rough E.R. modify proteins for secretion•Smooth E.R. contains enzymes that make lipids

RibosomeLocation•In nucleus, cytoplasm, and Rough E.R.

Function•Produce proteins following coded instruction that come from the nucleus

Golgi ApparatusLocation•Near E.R. and nucleus

Function•Stack of membranes that accept proteins produced by the rough E.R.•Contain enzymes that attach carbohydrates and lipids to proteins (“package proteins”)•Proteins then sent to final destinations

Plant VacuoleLocation•Saclike structure in the cytoplasmDescriptionPlant cells – Single, large central vacuoleFunction •Store materials such as water, salts, proteins and carbohydrates•Pressure in plant vacuole aid in support of plant cell (lack of water – wilting)

VacuolesLocation•Saclike structures in the cytoplasmDescriptionAnimal & Protists – Small, multiple vacuolesFunction •Store materials such as water, salts, proteins and carbohydrates•Remove excess water from cell (contractile vacuole)

LysosomeLocation•Throughout the cytoplasm of the cell•Rare in plant cells

Function•Small organelles filled with enzymes that break down lipids, carbohydrates and proteins from food into particles that can be used by the rest of the cell.•Also a “cell cleaner” to break down old organelles and dead pathogens.

© 2003 Encyclopedia Britannica, Inc.

MitochondriaLocation•Throughout the cytoplasm•More numerous in cells that have high energy requirements.Function•Organelles that release energy in the form of ATP from stored food molecules (glucose)

Cellular RespirationCellular RespirationNote: Mitochondria contain some of their own genetic info or DNA that is essential to the function of the mitochondrion.

Copyright © Pearson Education, Inc., publishing as Benjamin Cummings

ChloroplastsLocation•Found in cytoplasm of plants, some protists and bacteria

Function•Use energy from sunlight to make energy-rich food molecules (glucose).

PhotosynthesisNote: Chloroplasts contain some of their own genetic info or DNA that is essential to the function of the chloroplast.

CentriolesLocation•Paired structures just outside the nuclear envelope in the cytoplasm•Only in animal cellsFunction•During cell division, centrioles separate and take up positions on opposite sides of the nucleus •Help organize the spindle that separate the chromosomes

Cilia & FlagellaLocation•Both extend from the surface of the cell

DescriptionCilia – numerous, short, hair-like projectionsFlagella- one or two, longer whip-like structures

FunctionBoth used to propel individual cells through environment

Cilia

Flagella

Prokaryotes Eukaryotes

Cell membraneRibosomesCell wall

NucleusEndoplasmic reticulumGolgi apparatusLysosomesVacuolesMitochondriaCytoskeleton

Animal Cells Plant Cells

LysosomesCentriolesSmall vacuole

Cell membraneRibosomesNucleusEndoplasmic reticulumGolgi apparatusVacuolesMitochondriaCytoskeleton

Go to Section:

Venn Diagrams

Cell Wall

Chloroplasts

Large vacuoles