1. Chapter 3 3.1 Cell Theory 3.2 Organelles 3.3 Cell membrane
3.4 Passive transport
3.5 Active transport

2. 3.1 Cell Theory
Describe the scientific theory of cells (cell theory) and relate the history of its discovery to the process of science.

3. Cell Theory Early studies led to the development of the cell theory.
The cell theory grew out of the work of many scientists and improvements in the microscope
Hooke
Leeuwenhoek
Schleiden
Schwann
Virchow

4. Cell Theory More was learned about cells as microscopes improved
The cell theory is a unifying concept of biology

5. Cell Theory The cell theory has three principles
All organisms are made of cells
All existing cells are produced by living cells
The cell is the most basic unit of life

6. Cell Theory
Prokaryotic cells lack a nucleus and most internal structures of eukaryotic cells
All cells share certain characteristics
Cells tend to be microscopic
All cells are enclosed by a membrane
All cells are filled with cytoplasm
cell membrane
cell membrane
cytoplasm

7. cytoplasm
Cell Theory
There are two types: Eukaryotic cells and Prokaryotic cells
Eukaryotic cells have a nucleus and membrane bound organelles
Prokaryotic cells do not have a nucleus or membrane bound organelles
nucleus
organelles
cell membrane

8. Cell Theory
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9. 3.2 Cell Organelles
Compare and contrast the general structures of plant and animal cells. Compare and contrast the general structures of prokaryotic and eukaryotic cells.

10. Cell Organelles Cells have an internal structure
The cytoskeleton has many functions
Supports and shapes cell
Helps position and transport organelles
Provides strength
Assists in cell division
Aids in cell movement

11. Cell Organelles
Several organelles are involved in making and processing proteins
The nucleus stores genetic information
Many processes occur in the endoplasmic reticulum
Production of proteins and lipids
There are two types
Rough
Smooth

12. Cell Organelles Ribosomes link amino acids to form proteins
Ribosomes are found on the Rough ER and in the cytoplasm
Golgi Apparatus sorts and delivers proteins. Also packages proteins.
Vesicles store and transport material through the cell.

13. Cell Organelles Other organelles have various functions
Mitochondria supplies energy to the cell
Vacuoles are fluid filled sacs that hold material
Central vacuole is a large vacuole that is found in plant cells.
Lysosomes contain enzymes to digest material
Centrioles are tubes found in the centrosomes
Help divide DNA
Form cilia and flagella

14. Cell Organelles Plant cells have cell walls and chloroplast
Cell wall provides rigid support to plant cells
Chloroplasts convert solar energy to chemical energy

15. Cell Organelles
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16. 3.3 Cell Membrane
Relate structure to function for the components of plant and animal cells. Explain the role of cell membranes as a highly selective barrier (passive and active transport)

17. Cell Membrane Cell membranes are composed of two phospholipid layers
The cell membrane has two major functions
Forms a boundary between inside and outside of the cell
Controls passage of materials

18. Cell Membrane
The cell membrane is made of phospholipid bilayer (2 layers of phospholipids)
There are other molecules embedded in the membrane
This is called the fluid mosaic model
Is selectively permeable
Only certain molecules can enter and exit the cell

19. Cell Membrane
Chemical signals are transmitted across the cell membrane
Receptors are proteins that bind with ligands (molecules that send signals) and change shape
There are two types of receptors
Intracellular receptor is inside the cell
Membrane receptor is inside the membrane

20. Cell Membrane
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21. 3.4 Diffusion and Osmosis
Relate structure and function for the components of plant and animal cells. Explain the role of cell membranes as a highly selective barrier (passive and active transport).

22. Diffusion and Osmosis
Diffusion and osmosis are types of passive transport
Passive transport does not require energy and is the movement of molecules down a concentration gradient
There are two types of passive transport
Diffusion: movement of molecules
Osmosis: movement of water

23. Diffusion and Osmosis **** note to students****
Write down the definitions with this slide from the pictures
There are three types of solutions
Isotonic
Hypertonic
Hypotonic

24. Diffusion and Osmosis
Some molecules diffuse through transport proteins
Some molecules cannot easily diffuse across the cell membrane
Facilitated diffusion is diffusion through transport proteins

25. Diffusion and Osmosis
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26. 3.5 Active Transport, Endocytosis, Exocytosis
Relate structure and function for the components of plant and animal cells. Explain the role of cell membranes as a highly selective barrier (passive and active transport).

27. Active Transport, Endocytosis, Exocytosis
Proteins can transport materials against a concentration gradient
Active transport requires energy input from a cell and enables a cell to move a substance against its concentration gradient
Powered by chemical energy (ATP)
Cells use active transport to maintain homeostasis

28. Active Transport, Endocytosis, Exocytosis
Endocytosis and exocytosis transport materials across the membrane in vesicles
Endocytosis
A cell can import large materials through the use of vesicles
Phagocytosis is another name meaning “cell eating”
Exocytosis
The opposite of endocytosis where large materials are exported from the cell using vesicles

29. Active Transport, Endocytosis, Exocytosis
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