1. Cell Structure and Function
The relationship between structure and function is a cornerstone of biology!!!

2. Objectives/Warm-Up
SWBAT: State the similarities and differences in prokaryotic and eukaryotic cells
Warm-Up: Define the words “prokaryote” and “eukaryote” in your notes. . .

3. Answers to Warm-Up
Prokaryote: A unicellular organism with no nucleus or organelles
Unicellular = ONE cell only
Eukaryote: A multicellular organism with a nucleus and organelles
Multicellular = MANY cells

4. History of Cells
Cells were first viewed using microscopes over 150 years ago. . .

5. Robert Hooke: First to Observe Dead Cells
English scientist who examined thin slices of cork with a microscope
Observed that cork was composed of “cells”
Actually observed dead cork cells, not live cells

6. Hooke observed dead cork cells like the ones pictured below!!!
Hooke called these “cells” because they looked like the small cells or rooms that monks lived in at the monastery

7. Anton Van Leewenhoek
First to observe live cells by taking blood scrapings from his own teeth

8. Matthias Schleiden German scientist who worked with plants
Used a microscope to observe that all plants are made of cells

9. Schwaan
German scientist who used a microscope to observe that all animals are made of cells

10. Cell Theory
Observations by these scientists led to the development of the CELL THEORY.
The Cell Theory describes what we believe to be true about all life and all cells.

11. Three Statements of Cell Theory
All living things are made of one or more cells
Cells are the basic unit of structure and function in organisms
All cells come from existing cells.

12. Test Yourself!!! Answer the following questions. . .
TRUE OR FALSE:
Something can be alive and not be made of cells
Every living cell comes from another cell
Some organisms are not made of cells
FALSE
TRUE

13. All cells have. . .STRUCTURE
All cells need certain supports to survive:
- DNA- all cells have double helix DNA
Cell Membrane: outer covering of cell
Cytoplasm (also called cytosol): open space inside cell
Cytoskeleton: support beams that hold cell’s shape
Ribosomes: structures that help make proteins needed to survive

14. Preview It!!! Click here to learn about cell types!!!
Use this webpage to learn about 3 cell types. Notice how they are similar and how they are different.

15. Types of Cells There are TWO MAJOR TYPES OF CELLS: Prokaryotes
Eukaryotes
These cell types are different, but share many common structures

16. Prokaryotes Organisms made of only one cell
Simple structure and function
Example: Bacteria

17. Taking a closer look. . .

18. Parts of a Prokaryote. . .
1. Cell Wall: surrounds the cell and provides structure and support
Think of the cell wall as a fortress around a city – it gives structure and keeps out invaders!!!

19. Cell Membrane: Flexible boundary that lies inside the cell wall in prokaryotes.
Think of a cell membrane as a door – substances can enter or exit the cell through the membrane like we access a room through a door!!!

20. 3. Cytoplasm: fluid that fills a cell in which organelles are suspended
Think of cytoplasm as the air that fills a room – it seems to simply take up space, but without its presence, life would stop!!!
Cytoplasm is PURPLE in the above picture!!!

21. 4. DNA: All cells contain DNA, the genetic material for reproduction and maintenance
Think of DNA as the blueprints for the cell: they tell the cell how to build what it needs!!!

22. 5. Ribosomes: the site where amino acids are joined to make proteins for the organism.
Think of ribosomes as factories where proteins are assembled!!!

23. Eukaryotes Organisms made of many cells
Complex functions and many organelles
Examples: Plant and animal cells

24. Similarities to Prokaryotes:
Eukaryotes:
Some have a cell wall
All have a cell membrane
All have cytoplasm
All have DNA
All have ribosomes
EUKARYOTES ALSO HAVE COMPLEX ORGANELLES

25. What is an organelle?
An organelle is any structure found inside a cell that carries out a specific function
Each organelle has a job that it must do to keep the cell working!!!

26. Nucleus
The nucleus is the commanding center of a cell. It holds all the DNA for the cell.
Think of the nucleus as a locked safe: important genetic information (DNA) is kept here and is not allowed out!!!

27. Lysosomes
Lysosomes are small, round organelles that contain enzymes for digesting waste
Think of lysosomes as trash cans: they collect digest and recycle waste!!!

28. Vacuoles and Vesicles
Vacuoles and vesicles are organelles that store water and nutrients for a cell
Plant cells contain on large central vacuole that stores water and nutrients, while animal cells have many smaller vesicles/vacuoles.

29. Find it!
Locate the vacuole in the plant cell, and the vesicle in the animal cell.

30. Rough and Smooth Endoplasmic Reticulum (ER)
The endoplasmic reticulum (ER) is a series of channels used to transport proteins throughout a cell
Think of the ER as a conveyor belt in a factory – it moves substances from where they are made to where they are used

31. Rough ER is dotted with ribosomes, giving it a rough appearance
Take a closer look. . .
Rough ER is dotted with ribosomes, giving it a rough appearance
Smooth ER does
not have
ribosomes on it

32. Golgi Body
The Golgi Body looks like a stack of pancakes. Its job is to package and ship proteins before they are released from the cell. They are the ware houses of the cell.
Think of the Golgi Body as the post office – the Golgi Body makes sure proteins are ready to be “mailed” throughout the body!!!

33. Mitochondria
The mitochondria is the powerhouse of the cell. It is the site where all ATP (energy) is created to run cell activities.
Think of the mitochondria as a power plant – without it creating power, all work would stop!!!

34. Microtubules and Microfilaments
Microtubules and Microfilaments help give the cell its three-dimensional shape
Think of microfilaments and microtubules as the beams of a building: the beams provide support to the building, just like the microtubules and microfilaments provide support to a cell!!!

35. Chloroplasts
Plant cells contain chloroplasts for making energy from sunlight.
Think of chloroplasts as solar panels: they are used to make energy from the sun!!!

36. Interesting Fact. . . Chloroplasts are the site of photosynthesis.
Photosynthesis occurs in all plant cells – it is how plants make their own food.
Animal cells do not have cholorplasts for making food – this is why animals must eat food!!!

37. Structures for Movement
Both prokaryotes and eukaryotes have structures that help them move.
These structures are called cilia and flagella

38. Cilia
Cilia are short, numerous hairs on the surface of a cell that allow it to move and/or obtain food
Paramecium, a simple organism, has cilia all over its body

39. Flagella
Flagella are long, whip-like structures that help a cell move or obtain food
An example of a cell with a flagellum is a sperm cell: the flagellum is used to move towards the egg in order for fertilization to occur

40. Pseudopodia
Organisms like amoebas use temporary cytoplasmic extensions called pseudopodia to stretch and move

41. Identify It!!! Fill in the diagram in your notes using this picture

42. Test Yourself. . .
Try to answer the following questions WITHOUT LOOKING BACK AT YOUR NOTES. . .

43. Test Yourself #1
List the three points of Cell Theory.

44. Answer: Test Yourself #1
All living things are made of one or more cells
Cells are the basic unit of structure and function in organisms
All cells come from existing cells.

45. Test Yourself #2
What is the difference between a PROKARYOTE and a EUKARYOTE?

46. Answer: Test Yourself #2
A prokaryote is a simple organism with no nucleus and few organelles
A eukaryote is an organism with a nucleus and many organelles

47. Test Yourself #3
What is DNA, and where is it located inside a cell?

48. Answer: Test Yourself #3
DNA is the blueprint for all cell functions.
In eukaryotes, DNA is found in the nucleus

49. Test Yourself #4 List the functions of these organelles: Mitochondria
Ribosomes
Nucleus
Golgi Body

50. Answer: Test Yourself #4
Mitochondria -- Powerhouse of the cell, produces energy as ATP
Ribosomes – Site where proteins are created
Nucleus -- Site where DNA is located
Golgi Body – Packages proteins for distribution and release

51. Test Yourself #5
What are flagella, and what are they used for?

52. Answer: Test Yourself #5
Flagella are long, whip-like tails on certain cells that help them to move and to catch food.

53. Test Yourself #6
Can you identify the organelles that belong at the red question marks???

54. Answer: Test Yourself #6

55. Next Up. . .
Be sure to review all of your materials before taking a quiz with your teacher!!!