Chapter 4

1. Chapter 4 Structure and Function of the Cell!!! Cell - the smallest unit able to carry out all the life activities of an organism.

2. The History (4-1)The men you need to know about…. • 1500-1600s • Hans & Zacharias Jenseen – 1st to produce compound microscope

3. Robert Hooke -- scientist who saw cork (plant) through microscope and called the openings/pores “CELLS”.

4. Anton van Leeuwenhoek–Worked with lenses to create the most powerful microscope up to that time • Better magnification • Better resolution • 1st to observe living cells. (bacteria, protists) • Known as “Father of Microbiology”

5. 1800s • Schleiden – all plants composed of cells • Schwann – all animals composed of cells • Rudolph Virchow – all cells come from other cells • These three men developed what we now call the “cell theory”.

6. CELL THEORY 1. All living organisms are composed of one or more cells. 2. Cells are the basic units of structure and function in an organism. 3. Cells come only from the reproduction of existing cells.

8. Cell Diversity • Cells come in different shapes, sizes, and internal organizations. • Shape reflects function.

9. Three Domains of Life • Eukarya • Bacteria • Archaea

11. TWO BASIC TYPES OF CELLS: • Eukaryotes vs. Prokaryotes Organelles – intracellular bodies that perform specific functions. “mini-organs”

12. Prokaryotic Cell • NO membrane bound nucleus • Simple – no membrane bound organelles • Have DNA in “nucleoid” region • Smaller in size • Unicellular • Bacteria • Primitive (old)

14. Eukaryotic Cell • A “true” membrane bound NUCLEUS • Complex -many membrane bound organelles • DNA contained in nucleus • Larger in size • Unicellular and multicellular • Animal, Plants, Fungi, Protist • Not as old as prokaryotes

17. Presence of nucleus • Complexity • Size

18. What do all cells have? • Genetic Information • Nucleic Acids –DNA/RNA! • Eukaryotic Cell • Contained in nucleus • More complex, rod shaped • Prokaryotic Cell • Free floating • Simple, circular shaped

21. What do all cells have?Plasma membrane/cell membrane • Semi-permeable or Selectively-permeable • Allows some materials to pass in/out of the cell • It is composed of phospholipids bilayer. (nonpolar) • Also has proteins embedded within that act as “bridges” to allow larger materials to pass. • Covers cell surface, barrier, support, protection

22. Phospholipid bilayer behaves like fluid. (called Fluid Mosaic Model) • The lipids and proteins can move laterally within the bilayer, like boat on ocean. • Constantly changes

25. Ribosomes Responsible for building protein Look like small dots. Some ribosomes are free in cytoplasm and others attached to “rough” ER. What do all cells have? DNARNAProtein

26. What do all cells have? Cytoplasm • Region within the plasma membrane that suspends cell organelles • The “filler”

27. What do all cells have? • The 4 Macromolecules • Nucleic Acids • Genetic info • Proteins • Made by ribosomes (many different functions) • Lipids • In cell membranes • Carbohydrates • Energy (metabolism)

28. Nucleus • Contains the DNA • Chromatin/chromosomes • Control center (regulates instructions) Most prominent structure

29. Nuclear Envelope Also called nuclear membrane double membrane surrounding nucleus What makes up the Nucleus?

30. Chromosomes chromatin strands that coil up Genes Traits DNA “Code” ATTTGGCC What makes up the Nucleus?

32. Nuclear pores Small holes in the nuclear envelope. Allows RNA and other materials to pass in/out of membrane What makes up the Nucleus?

33. Nucleolus Inside the nucleus Synthesis of Ribosomes The ribosomes then pass through the nuclear pores to the cytoplasm. What makes up the Nucleus?

35. Mitochondria Cellular Respiration takes place in Mitochondria Produces useable form of ENERGY for cell. Converts organic molecules (carbs) to ATP.. Have their own DNA (genetic info) and ribosomes Double membrane organelle Organelles

39. Endoplasmic Reticulum “ER” System of membranous tubes and sacs Acts as a “HIGHWAY”, moving molecules (proteins) inside cell Two types: rough and smooth Organelles

40. With Ribosomes Rough ER

41. NO ribosomes Smooth ER

42. Golgi Apparatus Function: processing, packaging, and sending molecules such as proteins Surrounds materials in “vesicle”. Organelles

43. The Golgi body is like ER in that it is system of membranes/sacs. Works closely with Smooth ER and looks similar to it.

44. Lysosomes Vesicles produced by Golgi apparatus Contain digestive enzymes Get rid of unwanted materials, waste, damaged cells, etc. Organelles

45. Cytoskeleton Network of long protein strands located in the cytoplasm Framework…support for cell structure Give cell shape. Organelles

46. Microfilament Part of cytoskeleton Aid cell in movement Parts of Cytoskeleton

47. Microtubule Part of Cytoskeleton Hollow tubes made of protein (tubulin) Maintain cell shape Act as tracks to guide Parts of Cytoskeleton

48. Intermediate Filaments Rods that anchor nucleus and other organelles Parts of Cytoskeleton

49. How does a cell move? Cilia - hairlike organelles that extend from surface of the cell. There are many of these short hairs on outside. You have cilia in your respiratory tract!! Flagella - when the hairlike organelles are long and less numerous. Flagella found on sperm cells!

50. Flagella Cilia