1. Structure and Function cells overview

2. Section 1: Introduction to the Cell

3. Discovery of Cells The invention of the lens
Robert Hooke (1665): observed a thin slice of cork (dead plant cells) with a microscope. He described what he observed as “little boxes” (cells).

4. Discovery of Cells
Anton van Leeuwenhoek (1675): was the first person to observe living cells.

5. Microscopes
Magnification: refers to the microscope’s power to increase an object’s apparent size
Resolution: refers to the microscope’s power to show detail clearly

6. Light Microscope

7. Transmission Electron Microscope (TEM)

8. Transmission Electron Microscope (TEM)
Herpes Virus
Plant Root Cell

9. Scanning Electron Microscope (SEM)

10. Scanning Electron Microscope (SEM)

11. Scanning Electron Microscope (SEM)
Mosquito Head
200X 2000X

12. Scanning Electron Microscope (SEM)
Fly Eye

13. Scanning Electron Microscope (SEM)
Inside of Stomach
Surface of Tongue
Neuron

14. Scanning Electron Microscope (SEM)
Pollen
Yeast
Red Blood Cell, Platelet, and White Blood Cell

15. TEM vs. SEM
Viruses leaving a cell

16. The Cell Theory What is the cell theory?
1. All living things are composed of one or more cells.
2. Cells are organisms’ basic units of structure and function.
3. Cells come only from existing cells.

17. Cell Diversity- Size Smallest Cells: Biggest Cells: Longest Cells:
6 inches long, 5 inches wide, 3 pounds
Ostrich Egg

18. Surface Area to Volume Ratio
SA = 6lw
V = lwh
SA = 6 mm2
V = 1 mm3
SA/V = 6:1
SA = 24 mm2
V = 8 mm3
SA/V = 3:1
SA = 96 mm2
V increases faster than SA
V = 64 mm3
SA/V = 1.5:1

19. Cell Diversity- Shape Cells differ widely in shape.
Most cells are roughly cuboidal or spherical.

20. Eukaryotes vs. Prokaryotes
Eukaryotes (animals, plants, fungi, protists) and prokaryotes (bacteria) differ greatly in structure.

21. Prokaryotic Cell

22. Cell Organelles and Functions

23. Cell Wall
Function: boundary around the plant cell provides structure and support
made up of cellulose, proteins, and carbohydrates
Plants only

24. Cell Membrane
Function: selectively permeable boundary allowing for transport in and out of the cell
phospholipid bilayer
Found in Plants and Animals

25. Cytoplasm Gelatin-like fluid that lies inside the cell membrane
-surrounds the organelles
Plants and Animals

26. Nucleus
Function: -storage center of cell’s DNA -manages cell functions
Nuclear envelope surrounds the nucleus-allows ribosomes to move out of the nucleus
Plants and Animals

27. Nucleolus Makes ribosomes for the cell Location: inside the nucleus
Plant and animal

28. Chromosomes Contains genetic material (chromatin and DNA)
Location-in the nucleus
Plants and animals

29. Mitochondria Process involved=cellular respiration Plants and Animals
Function: -converts energy stored in food into usable energy for work
Process involved=cellular respiration
Plants and Animals

30. Ribosomes Function: makes proteins (protein synthesis)
Plants and Animals
Found free in the cytoplasm and attached to the endoplasmic reticulum

31. Endoplasmic Reticulum
Function: intercellular highway (a path along which molecules move from one part of the cell to another)
Two types:
Rough Endoplasmic Reticulum
Smooth Endoplasmic Reticulum
Plants and Animals

32. Rough Endoplasmic Reticulum
Rough Endoplasmic Reticulum (rER): makes large amounts of proteins to be exported from the cell
Covered with ribosomes

33. Smooth Endoplasmic Reticulum
Smooth Endoplasmic Reticulum (sER): involved in the synthesis of lipids
Not covered with ribosomes

34. Golgi Apparatus
Function: receives proteins from the rER and distributes them to other organelles or out of the cell
(receiving, processing, packaging, and shipping)
Plants and Animals

35. Lysosomes Structure: contains enzymes
Function: breaks down food particles, invading objects, or worn out cell parts
Animals only

36. Vacuoles Structure: a sac of fluid surrounded by a membrane
Very large in plants
Function: used for temporary storage of wastes, nutrients, and water
Animals=vesicles

37. Plastids-contains pigment or starch
There are three types of plastids in plant cells:
Chloroplasts (discussed on next slide)
Chromoplasts: synthesize and store pigments
Leucoplasts: store food such as starches, proteins, and lipids
Chromoplasts
Leucoplasts
Red Pepper
Flower

38. Chloroplasts
Function: photosynthesis (conversion of light energy to chemical energy stored in the bonds of glucose)
Plants only

39. Centrioles sets of triplet microtubules arranged in a ring
Exist in pairs
Function: centrioles play a major role in cell division (mitosis)
Animals only

40. Cytoskeleton
Structure: a network of thin, fibrous elements made up of microtubules (hollow tubes) and microfilaments (threads made out of actin)
Function: -acts as a support system for organelles -maintains cell shape
Animals only

41. Plant Cells vs. Animal Cells
Animal cells are very similar to plant cells except for the following major differences:
Animal cells do not contain chloroplasts
Animal cells are not surrounded by cell walls
The vacuoles in plants are much larger than those of animals

42. Animal Cell

43. Plant Cell

44. Microscope Pictures of a Plant Cell and an Animal Cell
Elodea
Human Cheek Cells

45. The following is a list of tissues that have specialized functions and demonstrate corresponding specialization of subcellular structure. Match the tissue with the letter of the cell structures and organelles listed to the right that would be abundant in these cells.
Tissues Cell Structures and Organelles
1. Enzyme (protein)-secreting A. plasma membrane
cells of the pancreas B. mitochondria
2. Insect flight muscles C. Golgi apparatus D. chloroplast
3. Cells lining the respiratory E. ER
passages F. cillia & flagella
4. White blood cells that engulf G. vacuole
and destroy invading bacteria H. ribosome
5. Leaf cells in cacti I. lysosome        

46. Hierarchy of Biological Order

47. Magic School Bus goes Cellular
Bill Nye and Cells

48. THE END!