1. Chapter 7 Cellular Structure and Function

2. 7.1 Vocabulary Cell Cell Theory Cell Membrane Nucleus Eukaryote
Prokaryote – page 193 & 580

3. Section 1 Life is Cellular
Standards: 2B.1, 2B.2
Objectives:
Relate advances in microscope technology to discoveries about cells.
Compare compound light microscopes with electron microscopes.
Summarize the principles of the cell theory.
Differentiate between a prokaryotic cell and a eukaryotic cell.

4. History of Cells
Robert Hooke in 1665 made the first light microscope and discovered cells.
Studied cork (oak bark)  “cells”
Cell - basic structural & functional unit of life
Smallest unit of life

5. Cell Theory Cell Theory –describes the properties of cells.
3 Major Principles:
All living things are made up of cells unicellular/multicellular organisms
Cells are the basic unit of structure and function in living things.
New cells are produced from existing cells cells grow and then divide

6. Cell Size

7. Microscope Technology
Microscopes  study cells in great detail.
Advancements in science = advancements in technology & better microscopes.
Increases magnification
Increases resolution

8. Compound Light Microscope
Use glass lenses and visible light
Each glass lens magnifies previous lens
Cells are often stained with dye to see better

9. Electron Microscope Greater magnification
Use magnets and electrons  black and white shaded image.
Specimen must be dead, sliced very thin, and stained with metals.
Electron Microscope Images
White Blood Cell Chases Bacteria

10. All Cells have …
Plasma Membrane (or cell membrane) – thin, flexible barrier that surrounds cells  controls what enters/leaves the cell.
Ribosomes and Cytoplasm
Genetic material  DNA
Processes to break down molecules for energy.

11. Prokaryotic Cells Smaller and simple
No nucleus  DNA is singular, circular chromosome that is exposed and not protected by a membrane
No membrane-bound organelles
Obtain energy from sun or chemicals
Most unicellular organisms  bacteria

12. Prokaryotic Cells

13. Eukaryotic Cells Larger and complex
Has ORGANELLES (special substructures)
Has NUCLEUS which contains & protects DNA  chromosomes (X)
Mostly multicellular organisms plants, animals, fungus
Some unicellular  algae (protist), yeast (fungus)

14. Eukaryotic Cells

15. Practice: Comparing Cells
Prokaryotes
Eukaryotes
Specialized Organelles
Need Energy
Ribosomes
Larger and complex
Grow, Reproduce, & Respond
Has Nucleus
Cytoplasm
Mostly Unicellular  BACTERIA
DNA
Mostly Multicellular  animals, plants
No Nucleus
Energy from sun or chemicals
Single, circular chromosome
Plasma (Cell) Membrane
Smaller and Simple

16. 7.2 Vocabulary Cytoplasm Endoplasmic Reticulum Organelle
Golgi Apparatus
Vacuole
Chloroplast
Lysosome
Mitochondria
Cytoskeleton
Cell Wall
Centriole
Lipid Bilayer
Ribosome
Selectively Permeable

17. Section 2 Cell Structure
Standards: 2B.1, 2B.2
Objectives:
Identify the structure and function of the parts of a typical eukaryotic cell.
Diagram components of plasma membrane and explain the function of each structure.
Compare/contrast different types of cells (prokaryotes/eukaryotes & animal/plant/fungus).

18. Cytoplasm Semi-fluid material outside of the nucleus.
Prokaryotes  all processes occur here
Eukaryotes  all processes occur in organelles; different processes can occur at the same time

19. Cytoskeleton
Supporting network of fibrous protein filaments that help cells maintain shape, support, movement, and anchorage for organelles.
Composed of microtubules and microfilaments

20. Nucleus Control center
Contains DNA (info used to make proteins for growth, function, & reproduction).
Nuclear Envelope (Nuclear Membrane)  double membrane that surrounds nucleus; has PORES to allow substances (proteins & RNA) to enter/exit

21. Ribosomes Nucleolus Manufacture proteins  protein synthesis
Non membrane bound
Some float freely in cytoplasm & some are attached to the rough ER
Composed of RNA & protein
Nucleolus
Site of ribosome production
Found in the nucleus

22. Endoplasmic Reticulum (ER)
System of folded sacs and interconnected channels that serves as the site for protein and lipid synthesis.
Transports materials
High surface area = more room for functions to occur
Two types:
Rough ER – attached ribosomes; produce proteins for export to other cells
Smooth ER – no ribosomes; synthesizes carbohydrates and lipids.

23. Golgi Apparatus (or Complex)
Flattened stack of membranes that modifies, sorts, & packages proteins into sacks called vesicles.
Vesicles fuse to plasma membrane  release proteins outside of the cell.

24. Vacuole
Membrane bound vesicle for temporary storage of materials within the cytoplasm.
Store water, food, enzymes, waste.
Plant Cells  large vacuole
Animal Cells  none or have very small vacuoles

25. Lysosomes
Vesicles that contain enzymes that digest excess or worn-out organelles and food particles.
Digest bacteria and viruses
Fuse with vacuole  dispense enzymes  digest waste.
Mostly found in animal cells

26. Centrioles
Made of microtubules that organize cell division  organizes chromosomes for division.
Located in cytoplasm near nucleus
Animal and Protists cell

27. Mitochondria “Powerhouse”
Convert sugars into usable energy  cellular respiration
Outer membrane and highly folded inner membrane  increase surface area for breaking down sugar.

28. Chloroplasts
Capture light energy and convert it to chemical energy  photosynthesis
Plant cells only
Thylakoids  disk-shape compartments inside
Contains chlorophyll  pigment that traps sunlight; gives plants green color

29. Cell Wall
Thick, rigid, mesh of fibers that surrounds the outside of the plasma membrane.
Made of cellulose (carbohydrate)  protects cell and gives extra support.
Most prokaryotes, plant and fungi cells (made up chitin)

30. Cilia and Flagella
Hair-like structures that project outside of the plasma membrane  allow for movement.
Composed of microtubules
Cilia  many & short hairs  Animal & Protists Cells
Flagella  less and longer; whip-like motion  Animals Cells

31. Bacteria and Fungal Cell
No chloroplast

32. Animal Cell

33. Plant Cell

34. Review Cell Structure Temporary storage ____ A) cytoskeleton
Cellular respiration ____ B) lysosome
Photosynthesis ____ C) mitochondria
Protein synthesis ____ D) cell membrane
Enzymes that digest ____ E) centriole
Many, small hairs ____ F) chloroplast
Framework for cell ____ G) ER
Cell division ____ H) ribosome
Thin, flexible barrier ____ I) vacuole
Protein & lipid synthesis ____ J) cilia

35. Review Cell Structure Basic unit of life____ K) nucleolus
Semi-fluid inside cell____ L) eukaryote
Produces ribosomes____ M) prokaryote
Control center____ N) organelles
Modifies and sorts proteins____ O) nucleus
Describes cells____ P) cell wall
Contains a nucleus____ Q) cell theory
Specialized structures ____ R) golgi
No Nucleus _____ S) cytoplasm
Layer around membrane _____ T) cell

36. How Proteins are Made Begins in nucleus…DNA  RNA
RNA and ribosomes leave nucleus (via pores)
RNA and ribosomes make proteins  each having a specific function
Rough ER transports proteins in vesicles  Golgi packages proteins in new vesicles  transported
Lysosome use proteins  enzymes
Mitochondria use proteins  energy

37. How Proteins are Made 1. Proteins are assembled on ribosomes.
2. Some proteins complete their assembly on the rough endoplasmic reticulum.
3. Proteins are carried to the Golgi apparatus in vesicles.

38. How Proteins are Made
4. The Golgi apparatus sorts and packages proteins.
5. Vesicles are shipped to their final destination.

39. Review How Proteins are Made
Nucleus
Rough endoplasmic reticulum
Ribosome
Protein
Smooth endoplasmic reticulum
Cytoplasm
Cell membrane
Vesicle
Golgi apparatus

40. Plasma Membrane
Plasma Membrane (or cell membrane) – thin, flexible barrier that surrounds cells  controls what enters/leaves the cell.

41. Plasma Membrane’s Functions
Homeostasis  maintaining balance = constant & stable
Selective Permeability (or Semipermeable)- allows some substances to pass through while keeping others out.
Controls what, how, when, and how much
Water
O2 Glucose
Waste CO2
Waste
Outside Membrane
Inside

42. Plasma Membrane Structure
Phospholipid Bilayer – 2 layers of phospholipids are arranged tail-tail  make a sandwich.
Exists in watery environment (inside & outside cell)
Many phospholipids  strong barrier

43. Plasma Membrane Structure
Mostly made up of phospholipids
Polar Head
Hydrophilic  “water loving”
attracted to water 1) 2)
Nonpolar Tails
Hydrophobic  “water fearing”
repel water

44. Phospholipid

45. Plasma Membrane Structure3)
Proteins
Transmit signals to inside cell
Support structures  gives cell its shape
Transport Proteins –tunnels in membrane  move substances or waste through

46. Plasma Membrane Structure4)
Cholesterol
Prevents phospholipid tails from sticking together  allowing fluidity.

47. Plasma Membrane Structure5)
Carbohydrates
Attach to proteins and stick out to help cells identify chemical signals.

48. Fluid Mosaic Model Plasma membrane in constant motion
Creates a “sea” in motion & a pattern (mosaic)

49. Review Plasma Membrane Structure
Proteins ____ f) transmits signals in cell
Carbohydrates ____ g) attract water
Cholesterol ____ h) transportation & structure
Polar Heads ____ i) repels water
Nonpolar Tails ____ j) maintains fluidity

50. Plasma Membrane

51. 7.3 Vocabulary Passive Transport – page 209 Diffusion
Facilitated Diffusion
Osmosis
Isotonic
Hypertonic
Hypotonic
Osmotic Pressure
Active Transport – page 212
Homeostasis

52. Section 3 Cell Transport
Standards: 2C.1, 2C.2, 2C.3
Objectives:
Explain the 3 processes passive transport: diffusion, facilitated diffusion, and osmosis.
Predict the effect of a hypotonic, hypertonic, or isotonic solution on a cell.
Explain the 3 processes of active transport: protein pumps, endocytosis, and exocytosis.

53. Passive Transport
Passive Transport – movement of materials across cell membrane WITHOUT ENERGY; follows concentration gradient (HighLow)
3 Types:
Diffusion
Facilitated Diffusion
Osmosis

54. 1) Diffusion
Diffusion – net movement of particles from area of many particles to area with fewer particles.
High  low concentration
No energy
Results in equilibrium
ex) oxygen and CO2

55. Diffusion in a Cell

56. 2) Facilitated Diffusion
Facilitated Diffusion – molecules pass through special transport proteins in membrane.
High  low concentration
No energy
ex) glucose

57. 3) Osmosis Osmosis – diffusion of water across a membrane.
High  low concentration
No energy
Osmotic Pressure – force that results in net movement of water into or out of cell.
Solute (substance being dissolved) is dissolved in the solvent (substance doing the dissolving)

58. Solution – Solute? Solvent?B A C

59. 3) Osmosis

60. 3) Osmosis Isotonic Hypertonic Hypotonic Shrinks Shrinks
Same amount of solute inside & outside cell
Hypertonic
More solute outside cell
Hypotonic
More solute inside cell
Solution
water
water
water
Animal
Cells
Swells
(Burst lyse)
Normal
Shrinks
vacuole
water
water
Plant
Cells
water
Normal
Shrinks
Swells

61. Osmosis Isotonic Hypertonic Hypotonic Blue  solvent (water)
Orange  solute
Osmosis
Isotonic
Hypertonic
Hypotonic

62. Review Osmosis A B C Water flows out and cell shrivels?
Water flows in and cell expands?
No net movement of water?
More solute inside cell?
Same solute concentration in and out?
More solute outside cell?

63. Review Osmosis - Isotonic? Hypotonic? Hypertonic?A B C

64. Review Passive Transport – Diffusion, Facilitated Diffusion, or Osmosis?B A C D
H2O

65. Active Transport
Active Transport – movement of substances across the membrane against a concentration gradient (LH) which REQUIRES ENERGY.
3 Types:
Protein Pumps
Endocytosis
Exocytosis

66. 1) Protein Pumps
Transport proteins change shape to force substances to move across cell membrane.
Low  high concentration
Requires energy  ATP
ex) calcium, potassium, sodium

67. Large Particles  require ENERGY
Endocytosis – substances enter cell by pinching membrane into a vesicle
Exocytosis – vesicle fuses to membrane and releases substances out of cell

68. Review Active Transport – Protein Pumps, Endocytosis, or Exocytosis?B C

69. 20.1 & 20.2 Vocabulary
Virus – page 574

70. Ch 20.1 Viruses Standards: 2B.3 Objectives:
Compare/contrast viruses and cells.
Explain why viruses need cells to reproduce.

71. Viruses
NON-LIVING particle made of proteins, nucleic acids, and lipids (sometimes)
No normal cell parts and organelles
Cause many diseases and used for research
Must use living cells to reproduce
Extremely small  must use electron microscope

72. How Viruses Infect Cells
Viruses are surrounded by proteins that coat the outside  capsid
Proteins on virus bind to receptor proteins on cell’s cell membrane
Cell recognizes proteins & allow virus in  cell is tricked
Viruses use their genetic info (RNA or DNA) to make more copies inside of the infected cell

73. RNA Virus  Common Cold
Once the cold virus has penetrated the host’s cells, it uses the host’s cellular machinery to replicate itself.
Copies are translated into new viral parts
The virus makes copies of its RNA
Parts assemble into new viruses and leave host cell

74. HIV (Human Immunodeficiency Virus) which causes AIDS (Acquired Immune Deficiency Syndrome)
Cytoplasm
A DNA copy of the viral RNA is made.
The copy is inserted into the host’s genome.
It is later transcribed and translated into new viral parts.
The parts assemble into new viruses and burst from the host cell.
DNA

75. Comparing Viruses and Cells
Viruses are parasites that depend entirely upon their living host to survive.

76. Review - Viruses Cells Viruses Living Non-Living Particle
Made of proteins, nucleic acids, and lipids (sometimes)
Contains DNA and/or RNA
Carry out NORMAL cell functions
Reproduces by itself
Organelles, Cytoplasm, Ribosomes
Obtain and use Energy
Respond to environment
INDEPENDENTLY grow and develop