EXSC 191 9th EditionExam # 1 Study Guide Lectures: 1 - 10Lecture 1 (January 15)Chapter 1Explain the difference between anatomy and physiology:Anatomy – the structure of body parts and their relationship to one another4 types: gross, surface, microscopic, and developmentalPhysiology – the function of the living systems*Function is dependent on structure, and structure determines function.What is homeostasis?Homeostasis is a dynamic state of equilibrium which maintains a relatively constant internal environment. When the body cannot restore homeostatic balance, disease can occur.How does the body maintain homeostasis?Our bodies maintain homeostatic balance through the use of negative and positive feedback systems.Negative feedback – restores balanceStimulus – receptor – afferent pathway – control center – efferent pathway – effectorExample: thermoregulation (increase in body temp causes sweat glands to secrete sweat and cool the body when the sweat evaporates)Positive feedback – magnifies the original stimulusSelf perpetuating. Example: tear in blood vessel (more and more platelets arrive at site)Lecture 2 (January 17)Chapter 2Catalyst – a substance which lowers activation energy, increases the rate of reaction, and is not consumed in the reactionEnzyme – a biological catalyst consisting of two parts: an apoenzyme and a cofactorReaction rates are influenced by- Temperature: ↑temp = ↑rate- Particle size: ↓size = ↑rate- Concentration of reactant: ↑conc. = ↑rate- pH: ↓pH = ↓rateEnergy forms: chemical (ATP → ADP), electrical (nerve impulses), mechanical (muscle contraction), radiant (light waves)Acid – a compound which donates an H+ ion to another compound (a base)Base – a compound which accepts an H+ ionpH scale – inverse and logarithmicacid: the more H+ ions, the lower (more acidic) the pHbase: the fewer H+ ions, the higher (more basic) the pHBuffer – a mixture of pH compounds that resist pH changes (convert strong acids/bases into weak ones)Example: carbonic acid (H2CO3) in the blood soaks up free H+ when blood pH is too lowand releases H+ when blood pH is too high.Lecture 3 (January22)Chapter 3What do cells do?- Segregation (by the plasma membrane)- Transport and digestionSegregationFluid mosaic model – the plasma membrane is a very thin structure composed of a double layer of lipid molecules with protein molecules dispersed in it.a) Phospholipid bilayeri. Polar head – hydrophilic, attracted to waterii. Non-polar tail – hydrophobic, avoid wateriii. Basic structure of a phospholipid molecule: phosphorus-containing head group (polar head), glycerol backbone, 2 fatty acid chains (tail)b) Cholesteroli. Stabilizes the membraneii. Maintains fluidity and flexibilityc) Glycolipidsi. Lipids with attached sugar groups that provide a means of self-identification for the celld) Integral membrane proteinsi. Most are transmembrane, and all have hydrophobic and hydrophilic regionsii. Are involved in transport by channels and carrierse) Peripheral membrane proteinsi. Not embedded in the lipid bilayerii. Are attached to integral proteinsiii. Are often enzymes and signaling proteinsf) Glycocalyxi. Sugar coating on the outside of a cellii. Branching sugar groups, attached to proteins facing extracellular spaceiii. Used in cell identification, adhesion, and water attraction*See figure 3.3 in textbookTransport and DigestionPassive Transporta) Simple diffusion – nonpolar and lipid-soluble substances diffuse directly through the membrane (lipid bilayer)b) Facilitated diffusion – substances are transported across the membrane either by binding to protein carriers in the membrane and carried across or by moving though protein channelsc) Osmosis – movement of water through a selectively permeable membrane from low solute concentration to high solute concentrationDiffusion – movement of a solute from an area of high solute concentration to low solute concentration down a concentration gradient- Rate is affected by slope of gradient and particle size (smaller particles = faster diffusion)- It’s a passive process- Hydrophobic membrane prevents free diffusionLecture 4 (January 24)What is tonicity?Tonicity is the ability of a solution to change the shape or tone of cells by altering their internal water volume.a) Isotonic – solutions with the same solute concentration as that of the cytosolb) Hypertonic – solution has greater solute concentration than that of the cytosolc) Hypotonic – solution has lesser solute concentration than that of the cytosolActive Transport - Metabolic energy is required from the cell to move substances.a) Primary – facilitated by a carrier protein and directly uses ATPb) Secondary - uses potential energy generated by the pump to move substancesNa-K Pump (Primary Active Transport Example) see fig. 3.10- ATP dependent- Uses integral carrier protein- The function of the protein is regulated by its shape- Phosphorylation modifies the shape/function by converting ATP to ADP- Sodium is released- Potassium is picked up- Dephosphorilization occurs and protein again changes shape- Potassium is released into cell- This creates an ion gradient (resting membrane potential)- 3 Na ions are moved and 2 K ions are movedSecondary Active Transport Example (see fig. 3.11)- Na+ carries glucose into cell against its concentration gradients- Anti-port: Na+ in, something else outLecture 5 (January 27)Vesicular TransportEndocytosis – cell membrane grabs something from the extracellular fluid, pinches off forming avesicle, and carries it into the cella) Phagocytosis – Pseudopods (receptors) engulf foreign matter, forming a vesicle around itcalled a phagosomei. Associated with immune cells (macrophages)b) Pinocytosis – cell samples the extracellular fluidi. Non-selective process (no receptors)ii. Most vesicles are protein coatedc) Receptor-Mediated Endocytosis – receptors bind to specific things in the extracellular fluid (ex: calcium)Transcytosis – moving something across the cell in a vesicle along the cytoskeletonExocytosis – contents of vesicle are released into the extracellular fluid when vesicle merges with membranea) V-snare on the vesicleb) T-snare on the membraneThese snares are complementary and bind together allowing the membrane to separate and release the contents of the vesicle.Identification of alien invadersCell-cell RecognitionGlycoproteins serve