1. Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slides 3.20 – 3.37 Seventh Edition Elaine N. Marieb Chapter 3 Cells and Tissues Lecture Slides in PowerPoint by Jerry L. Cook

2. Cellular Physiology: Functions of all cells Slide 3.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Most cells can carry out the following:  Digest foods  Metabolize (make new cells, break down old ones and make ATP)  Dispose of wastes  Reproduce  Grow  Move  Respond to a stimulus (irritability)

3. Cellular Physiology: 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  Works because there is solution inside (intracellular) and outside of the cell (interstial)

4. Cellular Physiology: Membrane Transport Slide 3.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Transport is by two basic methods  Passive transport  No energy is required  2 types: diffusion and filtration  Active transport  The cell must provide metabolic energy  2 types: solute pumping & bulk transport

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

6. 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  Selectivity is lost when the cell is damaged or dies – like when you get a strawberry and it weeps.

7. 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

8. Passive Transport Processes Slide 3.24a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Types of diffusion  Simple diffusion  Unassisted process (it just happens)  Must be lipid-soluble solutes or small enough solutes to pass through membrane pores  Fats, fat soluble vitamins, oxygen, carbon dioxide and chlorine ions

9. Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Types of diffusion  Osmosis – simple diffusion of water  Highly polar water easily crosses the plasma membrane  Facilitated diffusion  Substances require a protein carrier for passive transport  Glucose needs a protein to help it in to a cell because it’s not a lipid and it’s big

10. Passive Transport Processes Slide 3.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Types of diffusion  The three types of diffusion help move glucose, water, oxygen and carbon dioxide in and out of the cell  This saves cells an enormous amount of energy since diffusion requires no energy from the cell

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

12. 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  Generally only occurs across capillary walls, especially in kidneys  A pressure gradient must exist  Solute-containing fluid is pushed from a high pressure area to a lower pressure area

13. 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 (need to go from lower to higher [ ])  Two common forms of active transport  Solute pumping  Bulk transport

14. Active Transport Processes Slide 3.28a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Solute pumping (or active transport)  Amino acids, some sugars and ions are transported by solute pumps  ATP energizes protein carriers, and in most cases, moves substances against concentration gradients  Ex: sodium-potassium pump moves sodium out and potassium in to cell against gradients

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

16. Active Transport Processes Slide 3.29a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bulk transport  Exocytosis (exo = out)  Moves materials out of the cell  Material is packaged in a sac or vesicle  Vesicle migrates to plasma membrane  Vesicle combines with plasma membrane  Material is emptied to the outside  Ex: hormones, mucus, cell waste

17. Active Transport Processes Slide 3.29b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 3.11

18. Active Transport Processes Slide 3.30a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bulk transport  Endocytosis (endo = in)  Extracellular substances are engulfed or enclosed in a membranous vesicle by the plasma membrane  Types of endocytosis  Phagocytosis – cell eating  Pinocytosis – cell drinking

19. Active Transport Processes Slide 3.30a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Phagocytosis (cell eating)  The plasma membrane extends and captures large molecules  White blood cells and other cells have the job of engulfing bacteria, foreign debris and dead cells to keep us healthy  Pinocytosis (cell drinking)  Also called bulk phase endocytosis  All cells do this often to take in fluids containing dissolved proteins, fats & ions

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

21. Cell Life Cycle Slide 3.31 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Cells have two major periods  Interphase  Cell grows  Cell carries on metabolic processes  Cell division  Cell replicates itself  Function is to produce more cells for growth and repair processes

22. 2 Events of Cell Division Slide 3.33 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Mitosis  DNA duplicates; nucleus divides  Results in two daughter nuclei  Cytokinesis  Division of the cytoplasm  Begins when mitosis is almost done  Results in two daughter cells

23. Protein Synthesis Slide 3.37 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Gene – DNA segment that carries the blueprint for building one protein  Proteins have many functions  Building materials for cells  Help cells do things (antibodies, hormones)  Act as enzymes (biological catalysts)

24. Protein Synthesis Slide 3.37 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Every set of 3 bases gives the code for an amino acid (in the DNA or gene)  Ex: AAA = phenylalanine; CCT = glycine  DNA has the information in nucleus but messenger RNA takes the code to the ribosomes in the cytoplasm  RNA is essential for protein synthesis (rRNA and tRNA each have roles)