1. CELLULAR STRUCTURE AND FUNCTION

2. BIG IDEA Cells are the structural and functional units of all living organisms. Cells are the structural and functional units of all living organisms.

3. Cell Discovery and Theory Section 7.1 Section 7.1

4. MAIN IDEA #1 The invention of the microscope led to the discovery of cells. The invention of the microscope led to the discovery of cells.

5. Important Discoveries Robert Hooke- observed cork with the first microscope and coined the term “cellulae” meaning small rooms Robert Hooke- observed cork with the first microscope and coined the term “cellulae” meaning small rooms Anton van Leeuwenhoek- first to observe living organisms with a microscope Anton van Leeuwenhoek- first to observe living organisms with a microscope Both men led to many scientific discoveries (scientific revolution) Both men led to many scientific discoveries (scientific revolution)

6. Microscopes Compound light microscope- uses visible light and a series of lenses to create a magnified image. Compound light microscope- uses visible light and a series of lenses to create a magnified image.

7. Microscopes Electron microscope- uses magnets to beam electrons at thin specimens. Electron microscope- uses magnets to beam electrons at thin specimens. Only nonliving cells and tissues can be observed with electron microscopes Only nonliving cells and tissues can be observed with electron microscopes

8. Cell Theory One of the fundamental ideas of modern biology and includes the following three principles. One of the fundamental ideas of modern biology and includes the following three principles. 1. All living organisms are composed of one or more cells 2. Cells are the basic unit of structure and organization of all living organisms 3. Cells arise only from previously existing cells, with cells passing copies of their genetic material on to their daughter cells

9. Cell types Prokaryotic- cells without a nucleus OR membrane bound organelles (mostly unicellular). Prokaryotic- cells without a nucleus OR membrane bound organelles (mostly unicellular). Eukaryotic- have a true nucleus and membrane bound organelles. Eukaryotic- have a true nucleus and membrane bound organelles. Both have plasma membranes! Both have plasma membranes!

10. Eukaryotic structures Nucleus- distinct central organelle that contains the cell’s genetic material in the form of DNA. Nucleus- distinct central organelle that contains the cell’s genetic material in the form of DNA. Organelles- enable specialized cell functions to take place in different parts of the cell at the same time. Organelles- enable specialized cell functions to take place in different parts of the cell at the same time. Eukaryotes are thought to have evolved from prokaryotes- Endosymbiont Theory Eukaryotes are thought to have evolved from prokaryotes- Endosymbiont Theory

11. The Plasma Membrane Section 7.2 Section 7.2

12. MAIN IDEA #2 The plasma membrane helps to maintain a cell’s homeostasis. The plasma membrane helps to maintain a cell’s homeostasis.

13. Functions of the Plasma Membrane Creates a thin, flexible boundary that controls the movement of substances into and out of the cell Creates a thin, flexible boundary that controls the movement of substances into and out of the cell Selective permeability- capability to allow some substances pass through while keeping others out. Selective permeability- capability to allow some substances pass through while keeping others out.

15. Plasma Membrane Phospholipid bilayer- phospholipids are arranged in a double layer, TAIL TO TAIL. Phospholipid bilayer- phospholipids are arranged in a double layer, TAIL TO TAIL. Phospholipids have a polar head and two non- polar “tails.” Phospholipids have a polar head and two non- polar “tails.” Creates the barrier that is polar at its surface and non-polar in the center. Creates the barrier that is polar at its surface and non-polar in the center. Separates the inside and outside environments of the cell. Separates the inside and outside environments of the cell.

16. THINK ABOUT IT!!! How do hydrophobic substances cross a plasma membrane? How do hydrophobic substances cross a plasma membrane?

17. Other membrane components Transport proteins- move needed substances or wastes through the membrane. Transport proteins- move needed substances or wastes through the membrane. Cholesterol- non-polar molecule among the phospholipids; keeps the “tails” from sticking together- fluidity Cholesterol- non-polar molecule among the phospholipids; keeps the “tails” from sticking together- fluidity Carbohydrates (sugars)- help with cell identification Carbohydrates (sugars)- help with cell identification

19. Fluid Mosaic Model Phospholipids can move sideways across the membrane Phospholipids can move sideways across the membrane Other components can even move through/among the bilayer. Other components can even move through/among the bilayer. The fluidity of the membrane allows a scattered/random pattern arrangement of the components- mosaic. The fluidity of the membrane allows a scattered/random pattern arrangement of the components- mosaic.

20. Structures and Organelles Section 7.3 Section 7.3

21. MAIN IDEA #3 Eukaryotic cells contain organelles that allow the specialization and the separation of functions within the cell. Eukaryotic cells contain organelles that allow the specialization and the separation of functions within the cell.

22. Cytoplasm semifluid environment inside the plasma membrane. In ALL cells Prokaryotic- all chemical processes Eukaryotic- processes take place in organelles

23. Cytoskeleton Framework for the cell within the cytoplasm also aids in cell movement and other cellular activities. Framework for the cell within the cytoplasm also aids in cell movement and other cellular activities. ALL Eukaryotic cells ALL Eukaryotic cells Microtubules- long, hollow protein cylinders Microtubules- long, hollow protein cylinders Microfilaments- thin protein threads. Microfilaments- thin protein threads.

24. Cell Structures Nucleus- control center of the cell that contains coded directions for the production of proteins and cell division. Nucleus- control center of the cell that contains coded directions for the production of proteins and cell division. Surrounded by a nuclear envelope Surrounded by a nuclear envelope ALL Eukaryotic ALL Eukaryotic

25. Cell Structures Ribosomes- site of protein synthesis Made of 2 components Can be free floating OR attached to the ER Manufactured by the nucleolus ALL cells

26. Cell Structures Endoplasmic reticulum- highly folded membrane that is the site of protein and lipid synthesis ALL Eukaryotic Smooth- does NOT have ribosomes attached Rough- HAS ribosomes associated within

27. Cell Structures Golgi apparatus- a flattened stack of tubular membranes that modifies proteins and packages them for distribution outside the cell Golgi apparatus- a flattened stack of tubular membranes that modifies proteins and packages them for distribution outside the cell ALL Eukaryotic ALL Eukaryotic Vesicles= packages; fuses with plasma membrane Vesicles= packages; fuses with plasma membrane

28. Cell Structures Vacuoles- a membrane- bound vesicle for the temporary storage of materials Vacuoles- a membrane- bound vesicle for the temporary storage of materials Plant cells- ONE large Plant cells- ONE large Animal cells- a FEW small Animal cells- a FEW small

29. Cell Structures Lysosomes- a vesicle that contains digestive enzymes for the breakdown of excess or worn-out cellular substances. Animal cells ONLY

30. Cell Structures Centrioles- organelles that occur in pairs and are important for cell division Centrioles- organelles that occur in pairs and are important for cell division Animal cells Animal cells MOST protist MOST protist

31. Cell Structures Mitochondria- a membrane-bound organelle that makes energy available to the rest of the cell. Mitochondria- a membrane-bound organelle that makes energy available to the rest of the cell. ALL Eukaryotic cells ALL Eukaryotic cells

32. Cell Structures Chloroplasts- a double- membrane organelle with thylakoids containing chlorophyll where photosynthesis takes place. Plant cells ONLY

33. Cell Structures Cell wall- an inflexible barrier that provides support and protects the plant cell. Cell wall- an inflexible barrier that provides support and protects the plant cell. Plant cells Plant cells Fungi cells Fungi cells SOME Prokaryotes SOME Prokaryotes

34. Cell Structures Cilia and flagella- projections from cell surfaces that aid in locomotion and feeding. Cilia and flagella- projections from cell surfaces that aid in locomotion and feeding. Cilia- tiny hairs; SOME animal cells, protists cells, and Prokaryotes Cilia- tiny hairs; SOME animal cells, protists cells, and Prokaryotes Flagella- tail like; SOME animal cells, Prokaryotes, and some plant cells Flagella- tail like; SOME animal cells, Prokaryotes, and some plant cells

35. Cellular Transport Section 7.4 Section 7.4

36. MAIN IDEA #4 Cellular transport moves substances WITHIN the cell and moves substances INTO & OUT of the cell. Cellular transport moves substances WITHIN the cell and moves substances INTO & OUT of the cell.

37. Diffusion The net movement of particles from an area of high concentration to low concentration. The net movement of particles from an area of high concentration to low concentration. Dynamic equilibrium- condition, in which there is continuous movement but NO overall change Dynamic equilibrium- condition, in which there is continuous movement but NO overall change

38. Diffusion Factors that affect diffusion rate Factors that affect diffusion rate Concentration Concentration Temperature Temperature Pressure Pressure Ex: more collision= faster diffusion Diffusion does NOT require any energy! Diffusion does NOT require any energy!

39. Facilitated Diffusion Uses transport proteins to move other ions and small molecules across the plasma membrane. Uses transport proteins to move other ions and small molecules across the plasma membrane. Still from high concentration to low concentration! Still from high concentration to low concentration!

40. Osmosis Diffusion of water across a selectively permeable membrane. Also exhibits dynamic equilibrium

41. Isotonic Cell is in a solution that has the same concentration of water and solutes. Cell is in a solution that has the same concentration of water and solutes. Stable/Equilibrium Stable/Equilibrium

42. Hypotonic Cell is in a solution that has a lower concentration of solute. Cell is in a solution that has a lower concentration of solute. Net movement of water INTO the cell Net movement of water INTO the cell

43. Hypertonic The concentration of the solute outside of the cell is higher than inside. The concentration of the solute outside of the cell is higher than inside. Net movement of water is OUT of the cell Net movement of water is OUT of the cell

44. Active Transport The net movement of particles against a concentration gradient. The net movement of particles against a concentration gradient. Requires energy Requires energy Maintains homeostasis Maintains homeostasis

45. Na+/K+ Pump Uses ATP energy to transport three sodium ions out of the cell while moving two potassium ions into the cell. +++

46. Large Particles Endocytosis- intake of a substance Endocytosis- intake of a substance Exocytosis- secretion of a substance Exocytosis- secretion of a substance