This document discusses cell structure and function. It begins by defining prokaryotic and eukaryotic cells, then discusses the history of cell discovery. This led to the Cell Theory which states that all living things are made of cells, cells are the basic unit of life, and new cells are produced from existing cells. The document then describes the structures of prokaryotic and eukaryotic cells in detail, including their organelles and differences. It provides examples of cell types and concludes with self-test questions to check understanding.

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 FALSE

13. All cells have. . .STRUCTURE All cells need certain supports to survive: 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 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 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 and store 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 .

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 Smooth ER does not have ribosomes on it Take a closer look. . .

32. Golgi Body The Golgi Body looks like a stack of pancakes. Its job is to package and move proteins before they are released from 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. Identify It!!! Fill in the diagram in your notes using this picture

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

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

43. 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.

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

45. 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

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

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

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

49. 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

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

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

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

53. Answer: Test Yourself #6

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