Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Cell Diversity The Plasma Membrane Seventh Edition Elaine N. Marieb Chapter 3 Cells and Tissues Lecture Slides in PowerPoint by Jerry L. Cook

Cells Slide 3.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Carry out all chemical activities needed to sustain life  Cells are the building blocks of all living things  Cells are not all the same

Cell Diversity Slide 3.19a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.7; 1, 2

Cell Diversity Slide 3.19b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.7; 3

Cell Diversity Slide 3.19c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.7; 4, 5

Cell Diversity Slide 3.19d Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.7; 6, 7

Cells Slide 3.2 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  All cells share general structures  Cells are organized into three main regions  Plasma membrane  Nucleus  Cytoplasm  Cytosol + Organelles Figure 3.1a

Plasma Membrane Slide 3.7a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Barrier for cell contents – separates cytoplasm from the interstitial fluid  Double phospholipid layer  Hydrophilic heads  Hydrophobic tails  Other materials in plasma membrane  Proteins – integral and peripheral  Cholesterol  Glycoproteins

Plasma Membrane Slide 3.7b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.2

Plasma Membrane Specializations Slide 3.8a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Microvilli  Finger-like projections that increase surface area for absorption Figure 3.3

Plasma Membrane Specializations Slide 3.8b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Membrane junctions  Tight junctions  Desmosomes  Gap junctions Figure 3.3

Membrane Functions Slide 3.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Membrane Transport  Membrane Potential  Cell Recognition

Membrane Transport Slide 3.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Membrane Transport – movement of substance into and out of the cell through the membrane  Transport is by two basic methods  Passive transport  No energy is required  Active transport  The cell must provide metabolic energy

Solutions and Transport Slide 3.21 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Solution – homogeneous mixture of two or more components  Solvent – dissolving medium  Solutes – components in smaller quantities within a solution  Intracellular fluid – nucleoplasm and cytosol  Interstitial fluid – fluid on the exterior of the cell

Selective Permeability Slide 3.22 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The plasma membrane allows some materials to pass while excluding others  This permeability includes movement into and out of the cell

Passive Transport Processes Slide 3.23 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Diffusion  Particles tend to distribute themselves evenly within a solution  Movement is from high concentration to low concentration, or down a concentration gradient Figure 3.8

Passive Transport Processes Slide 3.24a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Simple diffusion  Unassisted process  Lipid-soluble materials (non-polar)  Ex: O 2, CO 2, fats, steroids, urea, alcohol  Solutes small enough to pass through membrane pores  Ex: H 2 O, Na +

Passive Transport Processes Slide 3.24a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Simple diffusion

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Osmosis – simple diffusion of water  Water easily diffuses across the plasma membrane from areas of high water concentration to areas of lower water concentration

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tonicity  Words that describe the solution surrounding a cell  Isotonic solutions  Have same H 2 O concentration as cell interior  No net movement of water  Most IV solutions  D 5 W (5% glucose in water)  Normal saline (0.9% NaCl in water)

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tonicity  Hypertonic solutions  Have lower H 2 O concentration than cell interior  Water moves out of cell  Cause crenation (shriveling up ) of RBC’s

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tonicity  Hypotonic solutions  Have higher H 2 O concentration than cell interior  Water moves into the cell  Causes cells to burst if very hypotonic  Examples  Distilled water  ½ Normal saline  ½ D 5 W

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Tonicity  Which type of solution would the doctor order for an extremely dehydrated patient?  Which type of solution would the doctor order for a patient with brain swelling?

Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Tonicity

Passive Transport Processes Slide 3.24b Facilitated diffusion  Substances require a protein carrier for passive transport

Diffusion through the Plasma Membrane Slide 3.25 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.9

Passive Transport Processes Slide 3.26 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Filtration  Water and solutes are forced through a membrane by fluid, or hydrostatic pressure  A pressure gradient must exist  Solute-containing fluid is pushed from a high pressure area to a lower pressure area  Occurs at kidneys’ filtration membrane

Active Transport Processes Slide 3.27 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Transport substances that are unable to pass by diffusion  They may be too large  They may not be able to dissolve in the fat core of the membrane  They may have to move against a concentration gradient  Two common forms of active transport  Solute pumping  Bulk transport

Active Transport Processes Slide 3.28a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Solute pumping  Amino acids, some sugars and ions are transported by solute pumps  ATP energizes protein carriers, and in most cases, moves substances against concentration gradients  Video

Active Transport Processes Slide 3.28b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.10

Active Transport Processes Slide 3.30a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bulk transport ( Video )  Endocytosis  Extracellular substances are engulfed by being enclosed in a membranous vescicle  Types of endocytosis  Phagocytosis – cell eating  Pinocytosis – cell drinking

Active Transport Processes Slide 3.30b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.12

Active Transport Processes Slide 3.29a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bulk transport  Exocytosis  Moves materials out of the cell  Material is carried in a membranous vesicle  Vesicle migrates to plasma membrane  Vesicle combines with plasma membrane  Material is emptied to the outside

Active Transport Processes Slide 3.29b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.11 Exocytosis – reverse of endocytosis

Membrane Potential Slide 3.29b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.11 Voltage across the membrane resulting from the separation of oppositely charged ions by the membrane. Na + and K + are constantly being pumped against their concentration gradients which maintains this voltage.

Cell Recognition Slide 3.29a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Glycocalyx - glycoproteins on surface of cell  Determine blood types  Binding sites for some toxins  Recognition of sperm by egg  Determines lifespan of cells  Immune response  Embryonic development

Cell Recognition Slide 3.29a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Glycocalyx