1. Cells
Module B
Lesson 1

2. Organisms An individual form of life All organisms have basic needs
Plant
Animal
Bacteria
All organisms have basic needs
Survive
Grow
reproduce

3. UNICELLULAR VS. MULTICELLULAR
UNIcellular- organism of only 1 cell that does all the jobs of the cell
Plankton
Yeast
Amoeba

4. UNICELLULAR VS. MULTICELLULAR
MULTIcellular- organisms made of several cells that have their own job to do
Plants
Animals

5. UNICELLULAR VS. MULTICELLULAR
Unicellular- divides to make new cells
Multicellular- divides to grow and replace old and dead cells

6. What are cells?
Smallest unit of life
Building blocks of life

7. Characteristics of Cells
They have different shapes
They have different parts – called organelles
Cells have different
functions (jobs)

8. Pseudonomonal Aeruginosa
Bacteria Cell
Streptococcus pyogenes
Bacteria Cell
Human Blood Cell
Escherichia Coli (E. Coli)
Bacteria Cell

9. Cell examples Blood cells Skin cells (top right)
Muscle cells (bottom right)
Brain cells (below)

10. Introduction to the Cell Cell Theory

11. 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).

12. Discovery of Cells
Anton van Leeuwenhoek (1675): was the first person to observe living cells.
He saw single- cell organisms swimming in pond water
He used a stronger microscope and was able to see unicellular organisms (bacteria and protozoa).

13. Observed the nucleus in plant cells

14. The Cell Theory Who developed the cell theory?
Matthias Schleiden (1838): concluded that all plants are composed of cells
Theodor Schwann (1839): concluded that all animals are composed of cells
Rudolph Virchow (1855): determined that cells come only from other cells

15. 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.

16. 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

18. Light Microscope

19. Light Microscope
Elodea - Aquatic Plant
40X 400X

20. Transmission Electron Microscope (TEM)

21. Transmission Electron Microscope (TEM)
Plant Root Cell

22. Scanning Electron Microscope (SEM)

23. Scanning Electron Microscope (SEM)

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

25. Scanning Electron Microscope (SEM)
Fly Eye

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

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

28. TEM vs. SEM
Viruses leaving a cell

29. Cell Diversity
Size
Shape
Internal Organization

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

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

32. ORGANELLES: Parts the Cell

33. Organelles
Structures in the cell’s cytoplast (fluid in the cell) that has its own shape and has a specific job in the cell

34. The Parts of the Cell
Each living cell carries out the tasks of taking food, transforming food into energy, getting rid of wastes, and reproducing.
Most eukaryotic cells have three main components:
Cell Membrane
Cytoskeleton
Nucleus

35. Nucleus
Structure: the nucleus is a sphere that contains another sphere called a nucleolus
Function: -storage center of cell’s DNA -manages cell functions

36. Cell Wall
Structure: rigid wall made up of cellulose, proteins, and carbohydrates
Function: boundary around the plant cell outside of the cell membrane that provides structure and support

37. Mitochondria Structure: folded membrane within an outer membrane
The folds of the inner membrane are called cristae
Function: -converts energy stored in food into usable energy for work
cellular respiration

38. Lysosomes
Structure: spherical organelles that contain hydrolytic enzymes within single membranes
Function: breaks down food particles, invading objects, or worn out cell parts

39. Chloroplasts
Structure: stacked sacs (thylakoids) that contain chlorophyll surrounded by a double membrane
Function: photosynthesis (conversion of light energy to chemical energy stored in the bonds of glucose)

40. Ribosomes Protein builders
Makes proteins necessary to repair damaged cells

41. Hierarchy of Biological Order

42. Hierarchy of Biology

43. Hierarchy of Biology Cells Tissues- group of cells working together
Organs- group of tissues working together
Organ system- 2 or more organs working together

44. Examples Cells Tissues- group of cells working together
Muscle tissue made of muscle cells
Skin tissue made of skin cells
Organs- group of tissues working together
Lungs, heart, stomach
Organ system- 2 or more organs working together
Nervous system
Muscular system

45. THE END!