1. Cell Structure and Function

2. Cells
Vary greatly in size and shape.
Unicellular
Multicellular

3. History of the microscope...
First seen in late 1500s (9x)
Light Microscopes (up to 1000x)
1950s - Electron Microscopes (million) (TEM, SEM)
1990s - Scanning Interferometric Apertureless Microscope (SIAM) (allows the imaging of individual atoms)

4. A little history... 1665 - Hooke (cork – “cells”)
Leeuwenhoek (living things)
1855 – Virchow (all cells come from other cells)
Schleiden (plant cells)
Schwann (animal cells)

5. Cells are the basic units of all life.
Cell Theory
Cells are the basic units of all life.
All organisms are made of one or more cells.
All cells arise from existing cells.
3.1

6. Cell Structure
Cell Membrane
Cytoplasm
Nucleus

7. Cell Membrane Controls what enters and leaves the cell. Phospholipid
Hydrophilic head
Hydrophobic tail
Lipid Bilayer
Fluid Mosaic Model (OVERHEAD)
Proteins
Partially or Completely through membrane

8. Cytoplasm
The semifluid substance between the membrane and the nucleus.
Made up of water and organic compounds.
Cytoskeleton: A network of protein fibers and tubes extending throughout the cytoplasm (structure and movement).

9. Nucleus The control center of the cell. Nuclear Envelope.
Pores in nuclear envelope.
Contains chromosomes.
Contains the nucleolus, an area which forms ribosomes.

10. Not all cells have a nucleus.
Prokaryotes: No nucleus.
Eukaryotes: Do have a nucleus.

11. Prokaryotes vs. Eukaryotes
No nucleus.
Small in size.
Less complex internal structure.
Bacteria and their relatives.
Considered the ancestor of eukaryotes.
Eukaryotes
Have a nucleus.
About 1000 times the volume of a prokaryote.
Most non-bacteria are made of eukaryotic cells.

12. Prokaryotic Cell Eukaryotic Cell Prokaryotic and Eukaryotic Cells
Section 7-1
Cell membrane
Cytoplasm
Prokaryotic Cell
Nucleus
Eukaryotic Cell
Organelles

13. Cell Organelles Ribosomes: Make proteins.
Rough Endoplasmic Reticulum (Rough ER): Make proteins.
Smooth Endoplasmic Reticulum (Smooth ER): Make lipids.
Golgi Apparatus: Molecules are packaged and transported.
Mitochondria: Power center. (ATP)
Lysosomes: Contain digestive enzymes.

15. Cilia and Flagella
Cilia: Short, hairlike projections (usually in large numbers) that are on the surface of a cell.
Flagella: A long, tail-like projection usually used by the cell for locomotion.
3.3

16. Plant Cells
Cell Wall: A tough, rigid outer covering that protects the cell and helps maintain its shape.
Chloroplasts: Make sugar from sunlight.
Vacuole: Large, membrane-bound container. Stores water, waste products, or ions.

17. Comparing Three Basic Cell Types
Prokaryotes: Bacteria.
Eukaryotes (plant)
Eukaryotes (animal)
3.4

18. Endoplasmic reticulum Endoplasmic reticulum
Venn Diagrams
Prokaryotes
Eukaryotes
Section 7-2
Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton
Cell membrane
Contain DNA
Animal Cells
Plant Cells
Cell membrane
Ribosomes
Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton
Cell Wall
Chloroplasts
Centrioles

19. Plant Cell Figure 7-5 Plant and Animal Cells Smooth endoplasmic
Nuclear
envelope
Ribosome
(attached)
(free)
Smooth endoplasmic
reticulum
Nucleus
Rough endoplasmic reticulum
Nucleolus
Golgi apparatus
Mitochondrion
Cell wall
Cell
Membrane
Chloroplast
Vacuole
Section 7-2
Plant Cell

20. Animal Cell Figure 7-5 Plant and Animal Cells (attached) Section 7-2
Centrioles
Nucleolus
Nucleus
Nuclear
envelope
Rough
endoplasmic
reticulum
Golgi apparatus
Smooth
Mitochondrion
Cell
Membrane
Ribosome
(free)
(attached)
Section 7-2
Animal Cell

21. Cells and Their Environment
How items get into and out of cells.

22. Semipermeable Membrane
Very small molecules (like water) can flow freely through the membrane.
Large molecules can only get in or out by using a protein “door”.
Very small molecules that are polar must also use a protein.

23. 2 Types of Transport
Passive Transport: No energy required. With the concentration gradient.
Active Transport: Energy being used to move something into the cell. Against the gradient.

24. Passive Transport
Diffusion: Molecules moving from an area of high concentration to low concentration.
Osmosis: The diffusion of water across a semipermeable membrane.

25. Osmosis can damage cells…
Hypertonic
(Water leaves cell.)
Isotonic
(Balanced.)
Hypotonic
(Water enters cell.)
Very Hypotonic
(Water enters, cell bursts.)

26. Diffusion
Solutes moving from an area of high concentration to an area of low concentration.

27. Diffusion
Solutes moving from an area of high concentration to an area of low concentration.

28. Diffusion
Solutes moving from an area of high concentration to an area of low concentration.

29. Diffusion
Solutes moving from an area of high concentration to an area of low concentration.

30. Diffusion
Solutes moving from an area of high concentration to an area of low concentration.

31. Diffusion, cont.
Small molecules diffuse faster than large molecules.
Increasing the temperature causes diffusion to occur more quickly.

32. Facilitated Diffusion
Molecules moving across the membrane with the assistance of a carrier protein but requiring no energy.
This is passive transport because it requires no energy!

33. 2 Types of Transport
Passive Transport: No energy required. With the concentration gradient.
Active Transport: Energy being used to move something into the cell. Against the gradient.

34. Active Transport
Moving solutes against a concentration gradient.

35. Active Transport, cont.
Carrier Proteins: Proteins in the membrane of the cell that bring out or take out large molecules.
Bulk Movement: Transporting large molecules (such as polysaccharides or proteins) across the cell membrane.

36. Bulk Movement Exocytosis: Transporting out of the cell.
Endocytosis: Transporting into the cell.
Pinocytosis: Cell drinking.
Phagocytosis: Cell eating.