Packet 2: Cell Structure and Function
2-1
Aim Introduction to Cells
(A) CELL THEORY
o The cell theory is a fundamental concept in biology that summarizes many
discoveries made by scientists regarding cells
o It states that:
1. All living things are made up of cells.
2.
Cells are the basic unit of structure and function in living things.
3.
New cells come only from pre-existing cells.
(B) PROKARYOTIC VS. EUKARYOTIC
o Cells fall into two main groups, based on whether they have a nucleus.
o A nucleus is the command center for the cell. It contains the DNA and controls all
functions of the cell.
PROKARYOTIC CELLS
Cell Membrane Yes
EUKARYOTIC CELLS
Yes
Nucleus
No
Yes
Cell Size
Small
Large
Complexity
Simple
Complex
Example
Bacteria
Muscle Cell