Chapter 3 The Cells: The Raw Materials and Building Blocks

1. Chapter 3 The Cells: The Raw Materials and Building Blocks

2. Multimedia Directory Slide 12 Cell Structure Video Slide 93 Cytology Video Slide 105 Handwashing and Gloving Techniques Video Slide 125 Lab Technician Video

3. Introduction Cells are basic building blocks of human body Cells come in different sizes, shapes, and types Blood cells, skin cells, and nerve cells all differ from one another, but form basis of the system There are many components that perform specific functions to keep cells alive Cells of similar type form tissues that function to work together in an organ, while organs perform special functions to create a system Systems work together to form functioning human body

4. Learning Objectives List and describe the various parts of a cell and explain their function and pathology Explain the process of cellular mitosis Describe cancer growth and staging Describe the types of active and passive transport within cells Explain cellular respiration and enzyme function and dysfunction Differentiate between bacteria, viruses, fungi, and protozoa and understand how these pathogens cause disease

5. Pronunciation Guide Benign Capsid Centrioles Centrosomes Chromatin Cilia Cytoplasm Deoxyribonucleic acid Diabetes Mellitus Endocytosis (bee NINE) (CAP sid) (SEN tree oles) (SEN tre soams) (CROW ma tin) (SILL ee ah) (SIGH tow plazm) (dee OK see RYE bow new clee ick a sid) (DIE ah bee teez Mel LITE us) (en Doe Sigh TOE sis) Click on the megaphone icon before each item to hear the pronunciation.

6. Pronunciation Guide (cont’d) Endoplasmic reticulum Exocytosis Flagella Fungi Golgi apparatus Hypercholesterolemia Lysosomes Malignant Metastasis Mitochondria Mycelia (EN doh PLAZ mic ri TIH cue lum) (EX oh sigh TOE sis) (flah GELL ah) (FUN jie) (GOAL jee app ah RA tuss) (HI per koh LESS tur ul ee me ah) (LIE she soams) (mah LIG nant) (meh TASS tah siss) (my the CAHN dree ah) (my SEE lee ah) Click on the megaphone icon before each item to hear the pronunciation.

7. Pronunciation Guide (cont’d) Organelles Organism Osmosis Phagocytosis Phenylketonuria Pinocytosis Protozoa Ribonucleic acid Ribosomes Vesicle (ore ga NELLS) (OR gan iz em) (ahz MOE sis) (FAG oh sigh TOH sis) (FIN ill KEE toe new ree ah) (pin oh se TOH sis) (pro tow ZOE ah) (rie bow new KLEE ic) (RIE beh Soams) (VESS ih kle) Click on the megaphone icon before each item to hear the pronunciation.

8. Overview of Cells Cells are formed from chemicals and structures Cells are found in all living things Some nerve cells can be 2 feet long or longer Cells can be flat, round, thread like, or irregularly shaped 7.5 trillion cells found in body work together to allow for proper functioning of body

9. Figure 3-1 Various types of cells within the human body.

10. Cell Structure Certain common traits that almost all cells share: Nucleus Organelles Cytoplasm Cell membrane

11. Figure 3-2 Cellular components.

12. Cell Structure Video Click here to view a video on the topic of cell structure. Back to Directory

13. Cell Membrane Defined boundary that possesses a definite shape and actually holds cell contents together, acting as protective covering Allows material in and out of cell Selectively permeable because they choose what gets in or out

14. Cell Membrane (cont’d) Has identification markers that identify it as coming from a certain person 3/10,000,000 of an inch thick

15. Figure 3-3 The cell membrane.

16. Transport Methods Moving things in and out of cell can be done in two broad ways: Passive transport: requires no extra form of energy to complete Active transport: requires some addition of energy to make it happen

17. Transport Methods (cont’d) Passive transport can be divided into four types: Diffusion Osmosis Filtration Facilitated diffusion

18. Diffusion Most common form of passive transport in which substance of higher concentration travels to area of lesser concentration Examples: Adding packet of powdered drink mix to pitcher of water Smell of classmate’s perfume filling room Necessary to move oxygen from lungs to blood stream, or carbon dioxide from blood stream to lungs

19. Figure 3-4 Two examples of diffusion.

20. Osmosis Another form of diffusion in which water travels through selectively permeable membrane to equalize concentrations of a substance Dissolved substance called a solute

21. Osmosis (cont’d) Water tends to travel across a membrane to equalize concentrations of a solute; ability of substance to pull water toward area of higher concentration called osmotic pressure The greater concentration of solute, the greater osmotic pressure, or pull, it exerts to bring in water

22. Figure 3-5Osmosis: Water moves from an area of lower concentrated solute to an area of higher concentrated solute.

23. Filtration Differs from osmosis in that pressure is applied to force water and its dissolved materials across membrane Similar to crush of people pushing through turnstile during rush hour Major supplier for forces in body is pumping of heart, which forces blood flow into kidneys, where filtration takes place

24. Figure 3-6The process of filtration in the kidneys, where smaller solutes such as the electrolytes sodium and potassium pass through the membrane, while the larger blood protein and cells normally do not.

25. Facilitated Diffusion Facilitated diffusion is a variation of diffusion in which a substance is helped in moving across the membrane, similar to an usher helping you to your seat Glucose is the substance that is often passed into our bodies It can be imagined as moving into an already revolving door – once it steps into the door it is pushed along

26. Figure 3-7 Facilitated diffusion.

27. Pathology Connection: Cystic Fibrosis Incurable, fatal genetic disease affecting 1/3000 Caucasian babies

28. Pathology Connection: Cystic Fibrosis (cont’d) Caused by malformation in membrane channels for chloride and sodium ions Sodium and chloride do not diffuse across cell membrane as they normally would Fluid around cells becomes extremely salty due to excess sodium and chloride Results in excessively thick mucus in respiratory, digestive, and reproductive systems; mucus can cause clogging in organs

29. Pathology Connection: Cystic Fibrosis (cont’d) Symptoms may include Difficulty breathing Nutritional deficits due to decreased absorption of nutrients Increased risk of respiratory infection Diabetes Infertility (especially in males)

30. Pathology Connection: Cystic Fibrosis (cont’d) Treatment No cure; treatments help extend and improve quality of life Nutritional supplements Antibiotics to prevent pneumonia Mucus thinning drugs With treatment today, average life span of patient is 35 years

31. Pathology Connection: Cystic Fibrosis (cont’d) Diagnosis Prenatal genetic testing Postnatal genetic testing Testing pulmonary function Testing amount of sodium in sweat

32. Pathology Connection: Diabetes Mellitus Common medical problem; main symptom (high blood sugar) caused by problem with facilitated diffusion Glucose transported into cells via facilitated diffusion Hormone insulin must be present in order for transport of glucose to occur Insulin is either absent, or cells insensitive to insulin Results in glucose not getting to cells like it should

33. Pathology Connection: Diabetes Mellitus (cont’d) Lack of glucose transport into cells causes several problems Lots of glucose hangs around in bloodstream, causing big osmotic problems for cells Cells can’t make as much energy as they need when glucose can’t be transported

34. Active Transport Can be broken down further to three different types: Active transport pumps Endocytosis Exocytosis

35. Active Transport Pumps Require addition of energy in form of ATP to move substance Energy needed because cell is trying to move substance into area that already has high concentration of substance Example: need to transport potassium into our cells, where high concentration already exists; it must be “pushed” in

36. Endocytosis Used by cells for intake of liquid and food when substance too large to diffuse across membrane

37. Endocytosis (cont’d) Substance is surrounded by small portion of cell membrane, forming chamber or vesicle which then separates from rest of membrane and moves into cell Phagocytosis: name for process if solid particle being transported Pinocytosis: name for process if water being transported

38. Exocytosis Transport of things out of cell Some cells produce substance needed outside cell Once substance is made, it is surrounded by membrane, forming a vesicle, and moves to cell membrane Vesicle becomes part of cell membrane and expels its load out of cell

39. Figure 3-8Types of active transport in and out of cells.

40. Table 3-1 Methods of Cellular Transportation

41. Pathology Connection: Familial Hypercholesterolemia Condition in which blood cholesterol too high; caused by poor diet and exercise or inherited Normally low density lipoprotein (LDL or “bad cholesterol”) binds to cholesterol, and allows it to be carried into cells via endocytosis; once inside, cholesterol used to make other lipids

42. Pathology Connection: Familial Hypercholesterolemia In familial hypercholesterolemia, LDL doesn’t move into cells, and stays in blood; causes two problems Too little cholesterol gets into cells, and cells must make more cholesterol LDL that cannot get into cells hangs around in blood; causes plaques in blood vessels which can lead to blood clots, strokes, and heart attacks

43. Pathology Connection: Familial Hypercholesterolemia (cont’d) Severe form Patients often have heart attacks or strokes as children Often fatal in children or teenagers Has no effective treatment

44. Pathology Connection: Familial Hypercholesterolemia (cont’d) Moderate form Leads to heart attacks and strokes, but usually not until mid-life Can be treated with diet modifications and cholesterol lowering drugs 1/500 Americans have moderate form

45. Cytoplasm Gel-like substance composed of water, nutrients, and electrolytes, which looks a lot like white of raw egg Required by cells for their internal environment in order for parts of cell, known as organelles, to thrive and function

46. Nucleus “Brains” of cell Dictates activities of other organelles in cell Has double walled nuclear membrane with large pores allowing certain materials to pass in and out, while preventing other materials from entering

47. Nucleus (cont’d) Chromatin Material found in nucleus that contains deoxyribonucleic acid (DNA); DNA contains blueprints, or specifications, for creation of new cells Will eventually form chromosomes, which contain genes Genes determine our inherited characteristics

48. Nucleus (cont’d) Nucleolus Spherical body made up of dense fibers found within cell nucleus Major function is to synthesize ribonucleic acid (RNA) that forms ribosomes

49. Figure 3-9The cell membrane, cytoplasm, nucleus, and nucleolus.

50. Ribosomes Organelles found on endoplasmic reticulum or found floating around in cytoplasm Made of ribonucleic acid (RNA) and assist in production of enzymes and other protein substances needed for cell repair and reproduction Can be considered “remodeler” of cell, taking existing structure and maintaining and repairing it