All living things are made up of small individual units that usually cannot be seen with the naked eye.  These units are called cells.  Some organisms consist of one cell, other are made up of many cells.  Whether one-celled (unicellular) or many-celled (multicellular) the life processes of the organism are carried on by its cells.

What where the contributions of Robert Hooke and Anton van Leeuwenhook to the development of the cell theory?
· Where the first people to look at living things under a microscope.
· Hooke called the structures he was looking at cells.
· Leeuwenhook looked at pond water and human blood.

What are the three major points in the cell theory?
· All organisms are made up of one or more cells
· All cells carry on life activities.  The life activities of a many-celled organism are the combined result of the activities of each cell.
· New cells arise only from other living cells by the process of cell division.

What is the difference between prokaryotic and eukaryotic cells?
· Prokaryotic cells are cells that lack any internal membrane bound structures.  No organelles. Bacteria
· Eukaryotic have many kinds of internal membrane-bound structures.  (organelles) Most importantly a nucleus.

Can cells grow to any size?  Why or why not?
· While some cells (chicken egg cell, nerve cells) may be very large, most cells can only reach a certain size.
· Cells need nutrients and these nutrients must be able to pass through the entire cell.  Wastes must also be pass out.

Eukaryotic cells have many specialized internal structures, called organelles.  Some organelles are enclosed in their own membrane while other organelles are not. 

Describe the following structures in a cell.  Be sure to include the function of each.

Cell wall -
· All plants, most bacteria, and some other cell contain cell walls.
· Provides shape and protection for cell.  Contains holes
· Made of cellulose.

Cell membrane -
· Two-layered structure made of proteins, lipids, and carbohydrates.  Proteins float in the lipids.
· Controls what enter the cell.
· Maintains a constant internal environment.  Homeostasis


Nucleus -
· Controls the cell.  Contains genetic material.
Nuclear envelope -
· Membrane that controls what enters and leave nucleus

Nucleolus -
· Located in the nucleus
· Made up of DNA, RNA, and proteins
· Site of ribosome production.

Cytoplasm -
· Watery material lying with the cell between the cell membrane and the nucleus.
· Holds organelles, site of many chemical reactions

Endoplasmic reticulum -
· Fluid filled canals enclosed by a membrane
· Provides transport system for the cell.
· Rough ER is lined with ribosomes, unlike smooth ER

Ribosomes -
· Site of protein synthesis.

Golgi Complex (bodies) -
· Stacks of flatten membranes
· Processing, packaging, and storage centers for the cell.

Lysosomes -
· Small sac-like structure that contains strong digestive enzymes. (hydrolytic enzymes)