http://koning.ecsu.ctstateu.edu/cell/cell.html

All 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.

A cell is the smallest unit that is capable of performing life

functions.

Amoeba Proteus

Plant Stem

Red Blood Cell

Nerve Cell

Bacteria

•Prokaryotic•Eukaryotic

Do not have structures surrounded by membranes

Few internal structures

One-celled organisms, Bacteria

http://library.thinkquest.org/C004535/prokaryotic_cells.html

Contain organelles surrounded by membranes Most living organisms

Plant Animal

http://library.thinkquest.org/C004535/eukaryotic_cells.html

http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif

http://waynesword.palomar.edu/images/plant3.gif

Organelles

Outer membrane of cell that controls movement in and out of the cell

It is semi-permeable i.e. let some substances to pass through while stops others.

http://library.thinkquest.org/12413/structures.html

Most commonly found in plant cells & bacteria

Made of a rigid material called cellulose

Supports & protects the cells

http://library.thinkquest.org/12413/structures.html

Directs cell activities Separated from cytoplasm by nuclear

membrane Contains genetic material - DNA

In nucleus Made of DNA Contain

instructions for traits & characteristics

http://library.thinkquest.org/12413/structures.html

Gel-like mixture

Surrounded by cell membrane

Site for chemical reactions such as respiration

Membrane-bound sacs for storage and digestion

Contains water solution

Help plants maintain shape

Some animal cells may have tiny vacuoles

http://library.thinkquest.org/12413/structures.html

Usually found in plant cells

Contains green chlorophyll

Where photosynthesis takes place

http://library.thinkquest.org/12413/structures.html

Cells with modified or improved designs

To enable them to perform a specific function

The following types of animal cells have adapted in order to better perform their function.

White blood cells Red blood cells Nerve cells Ciliated epithelial cells Smooth muscle cells

The following plant cells have adapted to do their job more efficiently

Root hair cells Palisade mesophyll cells Spongy mesophyll cells

A group of identical cells performing the same function form a tissue

Tissues of several type work together to make an organ

Some organs and tissues form organ systems

All organ systems work in harmony for the well being of the organism