Unit 4/Ch. 7 Cells

1. Unit 4/Ch. 7 Cells

2. Introduction to Cellsand the Cell Theory

3. Discovery of the Cell

4. They look like tiny empty rooms! Robert Hook (1665) Was the first to see cells…cork cells that is!

5. Antwon Van Leeuwenhoek (1674) I saw tiny moving things! They must be alive! First to see living cells!

6. Matthias Schleiden (1839) All plants are made of cells! German Botanist

7. Theodore Schwann (1839) All animals are made of cells! German Zoologist

8. Rudolf Virchow (1855) Stated that cells come from pre-existing cells. (Living things come from other living things!)

9. The Cell Theory • All living things are composed of cells. • Cells are the basic units of life. • New cells come from existing cells.

10. Exploring Cells using MicroscopesPurpose is to see a variety of cells and the differences.

11. The Compound light Microscope • Light passes through specimen • Can be used to observe living things • Can’t be used to observe molecules or viruses Image from: www. Biologycorner.com

12. Light microscope image of amoeba Magnified 100x

13. Light microscope image of cheek cells

14. Scanning Electron Microscope (SEM) • Beam of electrons scan surface of specimen • 3-D image • Views only dead specimen

15. SEM image of housefly

16. SEM of spider

17. Total Magnification=Eyepiece x Objective

18. Prokaryotes and Eukaryotes Notes

19. Prokaryotes • Small • Simplest • Evolved first • Less Complex • Genetic material (DNA) NOT contained in a nucleus • Example: Bacteria cells

20. Eukaryotes • Larger • More complex • Membrane bound structures • Genetic material is in a nucleus • Examples Include: protist, fungi, plant, and animal cells Image from: www.daviddarling.info/images/cell_structure.jpg

21. Prokaryotes and Eukaryotes • Both • Cell membrane • Ribosomes • Cytoplasm • DNA & RNA • Prokaryotes have circular DNA called plasmids • Eukaryotes have DNA in the Nucleus

22. Prokaryote & Eukaryote Size Comparison Prokaryotic cells are smaller than Eukaryotic cells.

23. Image from: www.phschool.com/.../images/cells/allcell.jpg

24. Exit Ticket • How is the total magnification power of a light microscope determined? • List the three parts of the cell theory. • What structure is found in eukaryotic cells that is not found in prokaryotic cells? • Give an example of a prokaryotic and a eukaryotic cell. • Name three things that ALL cells have.

25. Prokaryote and Eukaryote Drawings Draw, Color, Label and Descriptions Figure 7.2 A & B and Size Comparison Chart, Page 174 Write the Questions and Answers • Which is larger in size? (prokaryote/eukaryote) • Define prokaryote and eukaryote. • List 2 things they have in common. • List 2 differences they have.

26. Cell Parts and Functions

27. Prokaryote & Eukaryote Recap • Prokaryote---No true nucleus, smaller than eukaryotes, simple, no membrane bound organelles, circular DNA strands called plasmids, example: bacteria • Eukaryote--- True nucleus, larger than prokaryotes, complex, membrane bound organelles, DNA found in nucleus, example: plant and animal cells • Both---Ribosomes, DNA/RNA, cytoplasm, cell membrane

28. Organelles“little organs” • Specialized structures inside EUKARYOTIC cells • each structure has a job to do They’re likemini-organs! Model Animal Cell

29. Cytoplasm“Jello” • Gel-like substance holds the organelles in place Image from: www.cs.utexas.edu

30. Cell membrane“Gatekeeper” phosphate“head” • Function • separates cell from outside • Maintains homeostasis (semi-permeable) • controls what enters or leaves cell • recognizes signals from other cells • allows communication between cells • Structure (lipids & proteins) • double layer of fat • phospholipid bilayer • proteins lipid “tail”

31. Nucleus“Brain” • Contains cell’s DNA in the form of chromatin • Chromatin forms chromosomes during cell division • Surrounded by nuclear envelope • Contains small dense nucleolus (Site of Ribosome Synthesis) Nuclear envelope nucleolus Image from: www.cs.utexas.edu/.../src/images/nucleus.jpg

32. Ribosomes“Protein Factory” • Site of Protein Synthesis Image from: Genetics Education, Murdoch Children's Medical Research Institute

33. Endoplasmic Reticulum“TransportationSystem” • Rough ER – studded with ribosomes • Makes and transports lipids and proteins • Smooth ER – no ribosomes • Contains enzymes which make lipids

34. GOLGI BODY (APPARATUS/COMPLEX)“PostOffice” • Pancake- like membrane stacks • Sorts, and packages proteins for transport out of cell

35. LYSOSOMES“GarbageDisposal” • Membrane bound sacs that contain digestive enzymes. • They digest food or get rid of unwanted cell parts. www.emc.maricopa.edu/.../BIOBK/lysosomes.gif

36. Vacuoles“Storage” • Saclike structures that store water and other materials • Large central vacuole in plants • Contractile vacuole in single-celled organisms (paramecium) Image from: Benjamin Cummins Inc.

37. Mitochondria“Powerhouse” • Converts chemical energy in food into a useable form for the cell. (ATP) • Contains its own DNA • Cristae (folded inner membrane) INCREASES SURFACE AREA FOR ENERGY PRODUCTION DURING AEROBIC CELLULAR RESPIRATION

38. mitochondria chloroplast Mitochondria are in both cells!! animal cells plant cells

39. Chloroplast“Photosynthesis” • Capture solar energy and converts it into chemical energy (Glucose) during photosynthesis • Found in plant cells • Contains its own DNA

40. CELL WALL“Support/Protect” • Outside of cell membrane. • Found in plant, algae, fungi, and prokaryotic cells. • Plant cell walls made of cellulose.

41. PLANT CELLS • Cell wall • Chloroplasts • Bigger vacuoles • No centrioles

42. Proteins do all the work! one of the major job of cells is to make proteins, because… proteins do all the work! structural enzymes signals proteins DNA receptors cells DNA codes for proteins which are assembled by the ribosomes and used as enzymes for energy production at the mitochondria.

43. nucleus control cell protects DNA ribosomes make proteins cytoplasm jelly-like material around organelles central vacuole storage: food, water or waste cell wall support mitochondria make ATP in cellular respiration chloroplast make ATP & sugars in photosynthesis cell membrane cell boundary controls movementof materials in & out recognizes signals

44. PLANT CELLS • Cell wall • Chloroplasts • Bigger vacuoles • No centrioles

45. What structures do Animal Cells lack? Plant cells?

46. Exit Ticket • What cell organelle in an animal cell is responsible for maintaining homeostasis? • What is the primary function of a plant cell’s vacuole? • What two organic molecules make up the cell membrane? • What organelle in the cell is the site of protein synthesis? • What is the primary function of cytoplasm in plant and animal cells?

47. Give Me 5 Plant Cell & Animal Cell • Directions: Trace your hand, using a pencil, on the sheet of paper provided and cut it out. One side will be for a Plant Cell and the other side will be for an Animal Cell. On each finger(5), write one of the organelles listed and give its function. Draw each organelle in the palm of each hand to create a cell. • Be creative and color each side. • Organelles: • Plant Cell – Cell Wall, Nucleus, Mitochondria, Cytoplasm, Large Vacuole, Chloroplast, Endoplasmic Reticulum • Animal Cell – Nucleus, Mitochondria, Cytoplasm, Vacuole, Cell Membrane, Centrioles, Lysosomes An example is on the board This will be a project Grade

48. Specialized Cells Notes

49. Where do you think cells are located in our body? • EVERYWHERE!!! • Humans are made up of cells that work together and build muscle, bones, skin, and other organs.

50. All living things are made of building blocks called CELLS. • Humans, plants, animals, and bacteria are made up of one or many cells.