Cells are the basic unit of structure and function in living things. There are two main types of cells - prokaryotic cells which lack internal structures and eukaryotic cells which have internal membranes and structures called organelles. The organelles each have specific functions like the nucleus which controls cell processes, mitochondria which produce energy, and the endoplasmic reticulum and golgi apparatus which modify and transport proteins. Plant cells have additional structures like a cell wall, chloroplasts, and a central vacuole which allow them to perform photosynthesis and store nutrients.

1. Cell Structure and
Function
Chapter 7

2. Conversion Review
K H D ___ d c m
12.4m = ________cm
0.765L = ________mL
10,432ms = ________s

3. Going Further
1
Milimeter (mm) = 0.001m
 1 micrometer (μm) = 0.00001m (10-6m)
 1 nanometer(nm)=0.00000001m
(10-9m)

4. 7.1 Life is Cellular
Sizes of Objects and Magnifying Power of
Microscopes

5. Compound Light Microscope

6. Guidelines for using Light
Microscopes






Carry the microscope with one hand holding
the arm and the other hand supporting the
base.
Never slide the microscope across the lab
table.
Clean lenses with lens paper only.
Always begin AND end with the lowest power
objective in place and the stage at its lowest
level.
Use the coarse adjustment knob on low power
objectives.
Use ONLY the fine adjustment knob on high
power objectives.

7. The Discovery of the Cell
 Robert
Hooke
• Looked at cells in cork and named them cells
 Anton
van Leeuwenhoek
• Observed pond water
 Schleiden
and Schwann
• All plants and animals are made of cells
 Oken
and Virchow
• Cells are produced from division of existing
cells

8. Three Parts of the Cell Theory:
1.
2.
3.
All living things are made up of cells.
The cell is the most basic unit of life.
New cells are produced from existing
cells.

9. Why are cells so small?
Small cells function more efficiently than
large cells.
• All substances that enter and leave the cell
•
must cross the cell surface.
Cells need a high surface area to volume
ratio in order to exchange substances more
readily.

10. Prokaryotes
 Single-celled
organism that lacks a
nucleus and other internal
compartments.
 Bacteria are common prokaryotes.
Pearson Education inc. 2010

11. 
Common Features of Cells
•
•
•
•
Cell membrane – thin flexible barrier that
encloses and separates the cell from it’s
external environment.
Cytoplasm – the cell’s interior
Ribosomes – where proteins are made
Genetic Material – instructions for making
proteins, regulate cellular activities, and
enable reproduction

12. Eukaryotes
Cells that contain a nucleus and internal
compartments called organelles.
 Eukaryotic organisms can be one-celled
(unicellular) or contain many cells
(multicellular).

13. 7.2 Cell Structure

14. The Cytoskeleton
supports and shapes cell

helps position and transport organelles

provides strength

assists in cell division

aids in cell movement
Three types of cytoskeleton fibers:

•
•
•
Microfilaments – made up of protein and actin
Microtubules – made up of protein and tubulin
Intermediate fibers – thick ropes of protein

15. The Nucleus
Controls most functions of
the cell.

Most of the cell’s DNA
is contained in the
nucleus.

Surrounded by the
nuclear envelope,
which separates the
nucleus from the
cytoplasm.
•
The nuclear envelope
contains small channels
called nuclear pores
which allow substances
to move in and out of the
nucleus.

16. Nucleolus
Nucleolus
 Region
inside the
nucleus where
ribosomes are
assembled.

17. Ribosomes
 Located
free in the
cytoplasm or attached
to the rough
endoplasmic
reticulum
 Produce proteins

18. 2 types of endoplasmic reticulum (ER):
• Rough ER – has attached ribosomes and
thus has a rough appearance.
– Helps transport proteins from ribosomes in
vesicles.
• Smooth ER – performs various functions
such as making lipids and breaking down
toxic substances.
Rough ER
Smooth ER

19. Golgi Apparatus
Vesicle
 Modifies
proteins
received in vesicles
from the ER.
• Some vesicles will
remain in the cytoplasm
and become
lysosomes, which work
to remove waste in the
cell.

20. Vacuoles
 Used
for storage of water, salts, proteins,
and sugars.

21. Mitochondria

Harvest energy from organic
compounds to make ATP.

22. Cell Membrane
 Made
of a double layer of
phospholipids
• lipid bilayer
 Protects
and supports the
cell
 Regulates what enters and
leaves the cell
• Selectively permeable

23. Unique features of plant cells

Cell wall
•

Chloroplast
•

thick layer of protein and cellulose
surrounding the cell membrane.
use light energy to make carbohydrates from
carbon dioxide and water.
Central vacuole
•
•
takes up much of the plant cell’s volume
Stores water and nutrients.

24. Plant Cells

25. Plant Cell

27.  Cell
Specialization
• Cell Diversity