2. Microscopes provide windows to the world of the cell The light microscope enables us to see the overall shape and structure of a cell

3. Electron microscopes~ can view ultrastructures of cells They use a beam of electrons instead of light The greater resolving power of electron microscopes

4. The Cell Theory Robert Hooke (1600’s/ English)) used a compound light microscope to study cork, the dead cells of oak bark. Cells are the basic building blocks of all living things. Schleiden & Schwann (1830;s, German) their observations & conclusions are summarized as the cell theory

5. The cell theory is made up of three main ideas: 1.All organisms are composed of one or more cells. 2. The cell is the basic unit of organization of organisms. 3. All cells come from preexisting cells.

6. Why study cells? Cells  Tissues  Organs  Bodies bodies are made up of cells cells do all the work of life!

7. Cells have 3 main jobs make energy need energy for all activities need to clean up waste produced while making energy make proteins proteins do all the work in a cell, so we need lots of them make more cells for growth to replace damaged or diseased cells The Jobs of Cells Our organelles do all these jobs!

8. bacteria cells 2 Types of cells animal cells plant cells Prokaryote - no organelles Eukaryotes - organelles

9. Prokaryotic cells-Bacteria small, relatively simple cells oThey do not have a nucleus o enclosed by a plasma membrane and is usually encased in a rigid cell wall o Inside the cell are its DNA and other parts

10. Eukaryotic cells are partitioned into functional compartments All other life forms are made up of one or more eukaryotic cells These are larger and more complex than prokaryotic cells Eukaryotes are distinguished by the presence of a true nucleus The cytoplasm contains organelles Many organelles have membranes as boundaries These compartmentalize the interior of the cell This allows the cell to carry out a variety of activities simultaneously

11. Animal Cell

12. Plant Cell

13. Cell sizes vary with their function Cell size and shape relate to function

14. Cell size comparison Bacterial cell Animal cell  micron = micrometer = 1/1,000,000 meter  diameter of human hair = ~20 microns most bacteria  1-10 microns eukaryotic cells  10-100 microns

15. Natural laws limit cell size a cell must be large enough to house the parts it needs to survive and reproduce The maximum size of a cell is limited by the amount of surface needed to obtain nutrients from the environment and dispose of wastes

16. A small cell has a greater ratio of surface area to volume than a large cell of the same shape Surface area of one large cube = 5,400 µm2 Total surface area of 27 small cubes = 16,200 µm2 30 µm 10 µm

17. Organelles Organelles do the work of cells each structure has a job to do keeps the cell alive; keeps you alive Model Animal Cell They’re like mini-organs!

18. 1. Cells need power! Making energy to fuel daily life & growth, the cell must… take in food & digest it take in oxygen (O 2 ) make ATP remove waste organelles that do this work… cell membrane lysosomes vacuoles & vesicles mitochondria ATP

19. Function separates cell from outside controls what enters or leaves cell O 2, CO 2, food, H 2 O, nutrients, waste recognizes signals from other cells allows communication between cells Structure double layer of fat phospholipid bilayer receptor molecules proteins Cell membrane lipid “tail” phosphate “head”

20. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place

21. Vacuoles & vesicles Function moving material around cell storage Structure membrane sac small food particle vesicle vacuole filled w/ digestive enzymes vesicle filled w/ digested nutrients

22. Vacuoles have diverse functions in cell maintenance membrane-bound sacs with varied functions. Food vacuoles, from phagocytosis, fuse with lysosomes. Contractile vacuoles, found in freshwater protists, pump excess water out of the cell. Central vacuoles are found in many mature plant cells.

23. Food & water storage plant cells contractile vacuole animal cells central vacuole food vacuole

24. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage

25. Lysosomes small food particle vacuole digesting food lysosomes Function digest food used to make energy clean up & recycle digest broken organelles Structure membrane sac of digestive enzymes digesting broken organelles

26. A Job for Lysosomes 15 weeks 6 weeks

27. Connection: Abnormal lysosomes can cause fatal diseases Lysosomal storage diseases are hereditary They interfere with other cellular functions Examples: Pompe’s disease, Tay- Sachs disease

28. ENERGY-CONVERTING ORGANELLES

29. Function make ATP energy from cellular respiration sugar + O 2  ATP fuels the work of life Structure double membrane Mitochondria in both animal & plant cells ATP

30. lysosome  food digestion  garbage disposal & recycling cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage mitochondria  make ATP energy from sugar + O 2

31. Mitochondria make energy from sugar + O 2 cellular respiration sugar + O 2  ATP Chloroplasts make energy + sugar from sunlight photosynthesis sunlight + CO 2  ATP & sugar ATP = active energy sugar = stored energy build leaves & roots & fruit out of the sugars Plants make energy two ways! ATP sugar ATP

32. Chloroplasts found in plants and some protists convert solar energy to chemical energy in sugars

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

34. central vacuole  storage: food, water or waste mitochondria  make ATP in cellular respiration chloroplast  make ATP & sugars in photosynthesis lysosome  digestion & clean up cell wall  support cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material around organelles

35. 2. Cells need workers = proteins! Making proteins to run daily life & growth, the cell must… read genes (DNA) build proteins structural proteins (muscle fibers, hair, skin, claws) enzymes (speed up chemical reactions) signals (hormones) & receptors organelles that do this work… nucleus ribosomes endoplasmic reticulum (ER) Golgi apparatus

36. Proteins do all the work! cellsDNAproteins one of the major job of cells is to make proteins, because… one of the major job of cells is to make proteins, because… proteins do all the work! signals structural enzymes receptors

37. Nucleus Function control center of cell protects DNA instructions for building proteins Structure nuclear membrane nucleolus ribosome factory chromosomes DNA

38. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage mitochondria  make ATP energy from sugar + O 2 nucleus  protects DNA  controls cell chromosomes  DNA lysosome  food digestion  garbage disposal & recycling nucleolus  produces ribosomes

39. Ribosomes on ER Ribosomes Function protein factories read instructions to build proteins from DNA Structure some free in cytoplasm some attached to ER

40. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage mitochondria  make ATP energy from sugar + O 2 nucleus  protects DNA  controls cell ribosomes  build proteins nucleolus  produces ribosomes lysosome  food digestion  garbage disposal & recycling

41. Function works on proteins helps complete the proteins after ribosome builds them makes membranes Structure rough ER ribosomes attached Make membranes smooth ER Synthesizes lipids Endoplasmic Reticulum

42. lysosome  food digestion  garbage disposal & recycling cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage mitochondria  make ATP energy from sugar + O 2 nucleus  protects DNA  controls cell ribosomes  builds proteins ER  works on proteins  makes membranes

43. transport vesicles vesicles carrying proteins Function finishes, sorts, labels & ships proteins like UPS headquarters shipping & receiving department ships proteins in vesicles “UPS trucks” Structure membrane sacs Golgi Apparatus

44. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place vacuole & vesicles  transport inside cells  storage mitochondria  make ATP energy from sugar + O 2 nucleus  protects DNA  controls cell ribosomes  builds proteins ER  helps finish proteins  makes membranes Golgi apparatus  finishes, packages & ships proteins lysosome  food digestion  garbage disposal & recycling

45. central vacuole  storage: food, water or waste mitochondria  make ATP in cellular respiration chloroplast  make ATP & sugars in photosynthesis cell wall  support cell membrane  cell boundary  controls movement of materials in & out  recognizes signals Golgi apparatus  finish & ship proteins nucleus  control cell  protects DNA endoplasmic reticulum  processes proteins  makes membranes lysosome  digestion & clean up ribosomes  make proteins cytoplasm  jelly-like material around organelles nucleolus  make ribosomes

46. 3. Cells need to make more cells! Making more cells to replace, repair & grow, the cell must… copy their DNA make extra organelles divide the new DNA & new organelles between 2 new “daughter” cells organelles that do this work… nucleus centrioles

47. Centrioles Function help coordinate cell division only in animal cells Structure one pair in each cell

48. cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place mitochondria  make ATP energy from sugar + O 2 nucleus  protects DNA  controls cell ribosomes  builds proteins ER  helps finish proteins  makes membranes Golgi apparatus  finishes, packages & ships proteins lysosome  food digestion  garbage disposal & recycling vacuole & vesicles  transport inside cells  storage centrioles  cell division

49. THE CYTOSKELETON The cell’s internal skeleton that functions in cell structural support and motility A network of protein fibers makes up the cytoskeleton

50. three main types of fibers in the cytoskeleton: microtubules, microfilaments, and intermediate filaments. Microfilaments enable cells to change shape and move Intermediate filaments reinforce the cell and anchor certain organelles Microtubules give the cell rigidity provide anchors for organelles act as tracks for organelle movement MICROFILAMENT INTERMEDIATE FILAMENT MICROTUBULE

51. Cilia and flagella locomotor appendages that protrude from certain cells Clusters of microtubules drive the whipping action of these organelles

52. Cells have 3 main jobs make energy need food + O 2 cellular respiration & photosynthesis need to remove wastes make proteins need instructions from DNA need to chain together amino acids & “finish” & “ship” the protein make more cells need to copy DNA & divide it up to daughter cells Cell Summary Our organelles do all those jobs!