Chapter 3: Cells and Their Functions. Copyright 2013 Wolters Kluwer Health Lippincott Williams & Wilkins

Transcription

1 Chapter 3: Cells and Their Functions

2 Overview

3 Key Terms active transport cancer carcinogen chromosome cytology cytoplasm diffusion DNA filtration gene hemolysis hypertonic hypotonic interphase isotonic membrane potential mitochondria mitosis mutation nucleus organelle osmosis phagocytosis plasma membrane endocytosis exocytosis micrometer microscope ribosome RNA

4 The Cell Cytology The study of cells The Cell The basic unit of life Shows life characteristics Organization Metabolism Responsiveness

5 MICROSCOPES Learning Outcomes 1.List three types of microscopes used to study cells.

6 Microscopes Cytology The study of cells Microscope An instrument that magnifies structures not visible with the naked eye Types of microscopes: Compound light microscope Transmission electron microscope

7 Figure 3-1 Cilia photographed under three different microscopes. Which microscope shows the most internal structure of the cilia? Which shows the cilia in three dimensions?

8 Microscopes Checkpoints 3-1 What characteristics of life does a cell show? 3-2 Name three types of microscopes.

9 Microscopes Pop Quiz 3.1 Which microscope is most commonly used in laboratories? A)Scanning electron microscope B)Transmission electron microscope C)Compound light microscope D)Simple light microscope

10 Microscopes Pop Quiz Answer 3.1 Which microscope is most commonly used in laboratories? A)Scanning electron microscope B)Transmission electron microscope C)Compound light microscope D)Simple light microscope

11 Microscopes

12 CELL STRUCTURE Learning Outcomes 2.Describe the composition and functions of the plasma membrane. 3.Describe the cytoplasm of the cell, including the name and function of the main organelles.

13 Cell Structure General Cell Organization Plasma membrane Nucleus Cytoplasm Cytosol Organelles

14 Figure 3-2 A generalized animal cell, sectional view. What is attached to the ER to make it look rough? What is the liquid part of the cytoplasm called?

15 Cell Structure Plasma Membrane Encloses cell contents Regulates what enters and leaves cell Participates in many cell activities (e.g., growth, reproduction, cell-to-cell interactions) Plasma membrane components Phospholipid bilayer Cholesterol

16 Cell Structure Table 3-1 Proteins in the plasma membrane and their functions.

17 Figure 3-3 The plasma membrane. Why is the plasma membrane described as a bilayer?

18 Cell Structure

19 Cell Structure Plasma Membrane Membrane potential The difference in electric charge on either side of the plasma membrane Caused by separation of positive and negative ions and proteins on either side of the membrane Ion concentrations are determined by Channels Pumps Copyright 2013 allows Wolters Kluwer Health Williams & Wilkins Membrane potential the Lippincott plasma membrane to act

20 Figure 3-4 The membrane potential. What large, negatively charged ions contribute to the negative charge along the intracellular membrane?

21 Cell Structure Nucleus Largest organelle of cell Surrounded by nuclear membrane Contains Chromosomes Units of heredity; govern all cellular activity Nucleolus Assembles ribosomes

22 Cell Structure Cytoplasm Material between nuclear membrane and plasma membrane Cytosol Fluid portion of cytoplasm Organelles Specialized cell structures that perform different cell functions

23 Cell Structure Table 3-2 Cell parts (cytoplasmic organelles).

24 Cell Structure Surface Projections Structures that extend from the cell Cilia Short, hairlike projections Move fluids around cells Flagellum Long, whiplike extension from the cell Moves cell

25 Cell Structure Cellular Diversity Cell shape is related to cell function. A neuron s long fibers transmit electric energy from place to place in the nervous system. Small round red blood cells slide through tiny blood vessels. Cell organelle number is related to cell function. Lipid-producing cells have lots of smooth ER. Metabolically active cells have lots of mitochondria to manufacture ATP.

26 Figure 3-5 Cellular diversity. Which of the cells shown would best cover a large surface area?

27 Cell Structure Checkpoints 3-3 What is the main substance of the plasma membrane, and what are the three types of materials found within the membrane? 3-4 What is the membrane potential, and what types of substances maintain the membrane potential? 3-5 What are cell organelles? 3-6 Why is the nucleus called the cell s control center? 3-7 What are the two types of organelles used for movement, and what do they look like?

28 Cell Structure Pop Quiz 3.2 What is the main substance of the plasma membrane? A)Cholesterol B)Phospholipid C)Protein D)Steroid

29 Cell Structure Pop Quiz Answer 3.2 What is the main substance of the plasma membrane? A)Cholesterol B)Phospholipid C)Protein D)Steroid

30 Cell Structure Pop Quiz 3.3 Which organelle generates ATP? A)Centriole B)Golgi apparatus C)Mitochondrion D)Ribosome

31 Cell Structure Pop Quiz Answer 3.3 Which organelle generates ATP? A)Centriole B)Golgi apparatus C)Mitochondrion D)Ribosome

32 MOVEMENT OF SUBSTANCES ACROSS THE PLASMA MEMBRANE Learning Outcomes 4.Describe methods by which substances enter and leave cells that do not require cellular energy. 5.Describe methods by which substances enter and leave cells that require cellular energy. 6.Explain what will happen if cells are placed in solutions with concentrations the same as or

33 Movement of Substances Across the Plasma Membrane Selective Permeability Plasma membrane regulates what enters and leaves Travel across membrane is based on several factors Molecular size Solubility Electrical charge Types of travel Movement that does not require cellular energy

34 Movement of Substances Across the Plasma Membrane Movement That Does Not Require Cellular Energy

35 Figure 3-6 Diffusion of a solid in a liquid.

36 Figure 3-7 Facilitated diffusion. How would a change in the number of transporters affect a solute s movement by facilitated diffusion?

37 Figure 3-8 A simple demonstration of osmosis. What would happen in this system if the solute could pass through the membrane?

38 Figure 3-9 Osmotic pressure. What would happen to osmotic pressure if the concentration of solute were increased on side B of this system?

39 Movement of Substances Across the Plasma Membrane How Osmosis Affects Cells Another way to think about osmosis is in terms of solute concentration. Low Solute High Water Osmosis High Solute Low Water

40 Movement of Substances Across the Plasma Membrane Solutions and Their Effects on Cells

41 Figure 3-10 The effect of osmosis on cells. What would happen to red blood cells in the body if blood lost through injury were replaced with pure water?

42 Figure 3-11 Filtration.

43 Movement of Substances Across the Plasma Membrane

44 Movement of Substances Across the Plasma Membrane Movement That Requires Cellular Energy

45 Figure 3-12 Phagocytosis. What organelle would likely help to destroy a particle taken in by phagocytosis?

46 Figure 3-13 Exocytosis.

47 Movement of Substances Across the Plasma Membrane Checkpoints 3-8 What types of movement through the plasma membrane do not require cellular energy? 3-9 What term describes a fluid that is the same concentration as the intracellular fluid? What type of fluid is less concentrated? More concentrated?

48 Movement of Substances Across the Plasma Membrane Pop Quiz 3.4 Which process uses transporters but not ATP? A)Active transport B)Endocytosis C)Facilitated diffusion D)Simple diffusion

49 Movement of Substances Across the Plasma Membrane Pop Quiz Answer 3.4 Which process uses transporters but not ATP? A)Active transport B)Endocytosis C)Facilitated diffusion D)Simple diffusion

50 Movement of Substances Across the Plasma Membrane Pop Quiz 3.5 Which method transports bulk amounts of material into the cell using vesicles? A)Active transport B)Endocytosis C)Exocytosis D)Osmosis

51 Movement of Substances Across the Plasma Membrane Pop Quiz 3.5 Which method transports bulk amounts of material into the cell using vesicles? A)Active transport B)Endocytosis C)Exocytosis D)Osmosis

52 Movement of Substances Across the Plasma Membrane Pop Quiz 3.6 Cells crenate when they are placed in solutions that are A)Catatonic B)Hypertonic C)Hypotonic D)Isotonic

53 Movement of Substances Across the Plasma Membrane Pop Quiz Answer 3.6 Cells crenate when they are placed in solutions that are A)Catatonic B)Hypertonic C)Hypotonic D)Isotonic

54 PROTEIN SYNTHESIS Learning Outcomes 7.Describe the composition, location, and function of the DNA in the cell. 8.Compare the function of three types of RNA in cells. 9.Explain briefly how cells make proteins.

55 Protein Synthesis Overview Proteins give a cell its structure and function. DNA directs protein synthesis. Nucleotides make up DNA DNA organized into genes Genes organized into chromosomes RNA participates in protein synthesis but is not part of chromosomes.

56 Figure 3-14 Subdivisions of a chromosome.

57 Protein Synthesis Structure of DNA and RNA

58 Figure 3-15 Structure of DNA. Two of the DNA nucleotides (A and G) are larger in size than the other two (T and C). How do the nucleotides pair up with regard to size?

59 Protein Synthesis Role of RNA

60 Protein Synthesis Two-Step Process of Protein Synthesis Transcription First step; occurs in nucleus DNA code is transcribed into mrna by nucleotide base pairing Translation Second step; occurs in cytoplasm mrna leaves nucleus and travels to ribosomes Ribosomes and trna translate mrna into protein s 2013 Wolters Kluwer Health Lippincott Williams & Wilkins amino acid Copyright sequence

61 Figure 3-16 Transcription.

62 Figure 3-17 Translation.

63 Protein Synthesis Checkpoints 3-10 What are the building blocks of nucleic acids? 3-11 What category of compounds does DNA code for in the cell? 3-12 What three types of RNA are active in protein synthesis?

64 Protein Synthesis Pop Quiz 3.7 Which DNA nucleotide pairs with adenine? A)Cytosine B)Guanine C)Thymine D)Uracil

65 Protein Synthesis Pop Quiz Answer 3.7 Which DNA nucleotide pairs with adenine? A)Cytosine B)Guanine C)Thymine D)Uracil

66 Protein Synthesis Pop Quiz 3.8 Which RNA is transcribed from DNA? A)Amino acid B)Messenger RNA C)Ribosomal RNA D)Transfer RNA

67 Protein Synthesis Pop Quiz Answer 3.8 Which RNA is transcribed from DNA? A)Amino acid B)Messenger RNA C)Ribosomal RNA D)Transfer RNA

68 Protein Synthesis Pop Quiz 3.9 What is synthesized during translation? A)Amino acid B)Protein C)Starch D)Triglyceride

69 Protein Synthesis Pop Quiz Answer 3.9 What is synthesized during translation? A)Amino acid B)Protein C)Starch D)Triglyceride

70 CELL DIVISION Learning Outcomes 10.Name and briefly describe the stages in mitosis.

71 Cell Division Types of Cell Division Meiosis Produces gametes (n) Cuts chromosome number in half to prepare for union of egg and sperm during fertilization Mitosis Produces somatic cells (2n) Parent stem cell gives rise to two identical daughter cells

72 Cell Division Preparation for Mitosis DNA replicates during interphase Identical strands held together at centromere until they separate during mitosis DNA replication during interphase Mitosis

73 Cell Division

74 Cell Division Stages of Mitosis

75 Figure 3-18 The stages of mitosis. If the original cell shown has 46 chromosomes, how many chromosomes will each new daughter cell have?

76 Cell Division Checkpoints 3-13 What must happen to the DNA in a cell before mitosis can occur? During what stage in the cell life cycle does this occur? 3-14 What are the four stages of mitosis?

77 Protein Synthesis Pop Quiz 3.10 During which phase of mitosis are chromosomes first visible? A)Anaphase B)Metaphase C)Prophase D)Telophase

78 Protein Synthesis Pop Quiz Answer 3.10 During which phase of mitosis are chromosomes first visible? A)Anaphase B)Metaphase C)Prophase D)Telophase

79 Cell Division

80 Cell Aging As cells multiply, changes occur that may lead to their damage or death. Free radical injury Enzyme injury Gene mutation Slowing cell activity Apoptosis

81 CELLS AND CANCER Learning Outcomes 11. Discuss the role of cell changes in cancer, and list several cancer risk factors.

82 Cells and Cancer Development of Cancer Genetic mutations may cause uncontrolled cell division. Cells may spread (metastasize), producing cancer. Cancer cells form tumors, crowding out normal cells.

83 Cells and Cancer Cancer Risk Factors Heredity Chemicals Radiation Physical irritation Diet Viruses

84 Cells and Cancer Pop Quiz 3.11 Which of the following is a cancer risk factor? A)A diet rich in fruits and vegetables B)A family history of cancer C)Regular exercise D)Regular use of sunscreen

85 Cells and Cancer Pop Quiz Answer 3.11 Which of the following is a cancer risk factor? A)A diet rich in fruits and vegetables B)A family history of cancer C)Regular exercise D)Regular use of sunscreen

86 CASE STUDY Learning Outcomes 12. Use the case study to discuss the importance of cells to the functioning of the body as a whole.

87 Case Study Jim s lifestyle put him at risk of having a heart attack. Stress Overweight Sedentary High blood pressure During his heart attack, oxygen deficiency damaged Jim s cardiac muscle cells, making them unable to contract, which caused Jim s heart to stop beating.

88 WORD ANATOMY Learning Outcomes 13. Show how word parts are used to build words related to cells and their functions.

89 Word Anatomy

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