Download 3-1 cell

Section 3-1
“Cells”
Write everything that is
underlined
3.1 Cell Theory
KEY CONCEPT: Cells are the Basic unit
of life.
3.1 Cell Theory
The cell theory grew out of the work
of many scientists and improvements
in the microscope.
•
Many scientists contributed
to the cell theory.
3.1 Cell Theory
The Cell Theory:
1. All organisms are made of cells
•
3.1 Cell Theory
2. All existing cells are
produced by other living cells
3.1 Cell Theory
3. The cell is the most
basic unit of life
3.1 Cell Theory
•
All cells share certain characteristics:
–Cells tend to be microscopic.
–All cells are enclosed
by a membrane. (What carbon
based
cell membrane
molecule is found in that
membrane?)
–All cells are filled with
cytoplasm.
cytoplasm
Bacterium
(colored SEM; magnification
3.1 Cell Theory
There are two cell types:
1. Eukaryotic cells:
• Have a nucleus
• Have membranebound organelles
• Usually multi-cellular
•
•
Example:
plants, animals
cell membrane
3.1 Cell Theory
2. Prokaryotic cells:
• Do not have a nucleus
• Do not have membrane-bound
organelles
• Usually single-celled
• Example: bacteria
cell membrane
3.1 Cell Theory
Viruses
MICROSCOPIC PARTICLES THAT
INVADE CELLS, OFTEN
DESTROYING THEM
SMALLEST ORGANISMS IN THE
WORLD
3.1 Cell Theory
Viruses Are Not Alive
VIRUSES ARE NOT CELLS!
DO NOT USE ENERGY
CANNOT REPRODUCE BY THEMSELVES
MUST INJECT GENETIC MATERIAL INTO
CELL, CELL THEN FORCED TO MAKE
NEW VIRUSES
BACTERIOPHAGE
•
VIRUSES THAT ATTACK BACTERIA
3.1 Cell Theory
Virus Structure
CORE GENETIC
MATERIAL(DNA OR RNA)
PROTEIN COAT/HEAD
(PROTECTS DNA)
SHEATH
TAIL FIBERS
ENDPLATE
ENZYMES (NEEDED TO
START REPRODUCTION
WITHIN HOST CELL)
3.1 Cell Theory
Virus Reproduction
VIRUS COMES INTO CONTACT WITH
CELL
INJECT GENETIC MATERIAL INTO CELL
CELL BECOMES VIRUS MAKING
MACHINE
3.1 Cell Theory
Activity
On a blank sheet of paper write down and answer the
following questions:
1.
2.
3.
4.
Summarize the cell theory
What do all cells share?
Explain the differences between a
Prokaryotic and Eukaryotic Cell. Give
an example of each.
What makes a virus not alive?
How do viruses reproduce?
5.
On the other side of the paper split the paper in half.
Draw, color and label a Prokaryotic Cell and a Virus!