BY 124 1st Edition Lecture 16Outline of Last Lecture Chapter 41 (cont.)I. In stomachII. Hormones III. Small intestineIV. Other organs used in digestiona. Liver b. Gall bladderc. Biled. Pancrease. Cecumf. Large intestineV. Nutrition Outline of Current Lecture I. RespirationII. 2 classes of respiratory surfacesIII. Marine organismsIV. Terrestrial organismsV. Nose VI. PharynxVII. LarynxVIII. EsophagusIX. TracheaThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.X. LungsXI. How do you breathe?XII. Important termsXIII. BirdsXIV. Circulatory SystemXV. Veins XVI. HeartCurrent LectureChapter 42 I. Respirationa. Small animals - Diffusion across moist membraneII. 2 classes of respiratory surfacesi. Outward oriented – outside of body1. parapodiaii. Inward oriented – inside creature1. Lungsb. 4 things in commoni. Have to stay moistii. Need large surface areaiii. Have to have a way to take oxygen from those structures to other cells of bodyiv. Need protectionIII. Marine organismsa. Gillsb. Countercurrent exchange mechanism – Figure 42.23i. Operculum pumps water into gillsii. Oxygen moves from water into blood because water and blood are flowing in opposite directionsiii. Uses concentration gradients to transfer oxygen into bloodiv. By running in opposite directions, it increases the amount of oxygen that can be absorbed by blood1. If they were running concurrent then they would not be able to absorb as much. 50% would be as much as it could absorb IV. Terrestrial animalsa. Easier to breathe on landb. Two types of respiratory systemsi. Tracheal system – figure 42.241. No true organs associated with it, mainly just ducts/tubulesa. Cartilagenous rings hold tubes open2. Only in small animals like insects3. Bigger insects have wings and this allows them to get more oxygeninto their bodies which allows them to stay largeii. Lungs – figure 42.251. Primitive fishes, most amphibians, all reptiles, birds, mammals2. External respirationa. Exchange oxygen from air into blood which then moves into tissue fluid3. Internal respirationa. Out of circulatory system into cellb. Into cell → Electron Transport Chain →ATPc. ****Main reason for oxygen intake is for ATP production using the electron transport chaind. Modified nostrilsV. Nosea. Hair in nose i. Filter airii. Warm airb. Mucosa lining – moistens airVI. PharynxVII. Larynx – “”voice box”a. Ligaments in voice box vibrate to cause soundsb. Length, thickness, and degree of elasticity alter pitch of voicei. Testosterone changes elasticity to deepen voiceVIII. Esophagusa. Epiglottis covers glottisIX. Tracheaa. Upward pointing ciliai. Used to catch things from going into lungs1. Cough outii. Can be restored if destroyedX. Lungsa. Branches into Bronchus which branches further into bronchioles that will have alveoli on ends i. Alveoli – “little sac”1. Covered by capillaries2. Only one cell thick to allow for faster diffusion3. Simple diffusiona. As soon as air moves into lungs, it will immediately start to get into blood stream by capillaries4. Lined with film of lipoprotein which reduces surface tension of alveolia. Keeps them from collapseb. Only made at very end of embryonic developmenti. Premature babies lack this protein at firstb. Provides oxygen for heartc. Surrounded by pleural membranesi. Like a double-walled sac1. One adheres to lung and one adheres to body cavity wallXI. How do you breathe?a. Increase in CO2 and increase of hydrogen ions which decreases pH and is sensed in bloodb. Breathing control centers in pons and medulla oblongata sense above conditionsc. We breathe by negative pressurei. Air is pulled in not pushedd. Sensed by nerves in diaphragm which tells rib cage to open and expand chest cavitye. Atmospheric pressure is lower than that inside lungsf. Back-up system: Chemo receptors in aorta and carotid arteries are looking for low oxygen levelsi. Carotid – goes to brainii. Aorta – comes from lungsg. Stretch alveoli which stimulates receptorsi. Stops sending oxygenh. Exhale i. Rib cage gets smaller which deflates lung and ribcageXII. Important terms to know dealing with lungs/breathinga. Tidal air – volume of air taken in or out with a single breathb. Vital capacity – max volume of air that can be inhaled/exhaled during forced breathingc. Residual volume – air that remains in lungs when you force out all that you canXIII. Birds a. Different type of respiratory system – air sacsb. Parabronchi not alveolic. One-way systemi. Fills air sacs and then fills lungsd. 1st inhale moves into lungs upon first exhale e. 2nd inhalation moves into air sacs and exhaled upon 2nd exhalationXIV. Circulatory systema. Open and closed (Figure 42.3)i. Insects – open 1. Long tube that runs down body that has a pump that pumps hemolymph (blood + interstitial fluid) into heart and pools which bathes tissues. Does not carry oxygen (only located in tracheal system)ii. Humans – closed1. Blood is totally separated from interstitial fluid and moves into heart which transports blood through small bronchial tubesb. Figure 42.9c. Figure 42.10i. Arteries1. Go away from heart2. Arteriole – small arteryii. Capillariesiii. Veins1. Go towards heart2. Venule – smaller veiniv. Composition1. Connective tissue2. Smooth muscle3. Simple squamous lining of endothelial layer4. Endothelium5. Basal lamina (only in capillaries?)d. Figure 42.14 – capillary bedsi. Blood moves into capillary beds with a lot of surface area. Velocity slows and blood pressure decreases from arteries to veinsii. Things can leave by:1. Clefts or openings between cells2. Simple diffusion3. Vesiclesiii. When sphincters are contracted, it narrows down capillary bed to a singlerouteiv. When sphincters are relaxed, more capillary beds are openv. Usually open most during digestione. Figure 42.15 – how things leavei. Blood pressure (hydrostatic pressure) is highest on arterial side. Thereforeit pushes things out like water, glucose, etc1. Things that won’t leave are blood cells and proteins because they are too bigii. Osmotic pressure – ability for something to take up water 1. Water leaves because of blood pressure but will ultimately come back in because of the concentration gradient2. The water that does not return is interstitial fluid but it will come back eventually f. Vascular shock results from too much water XV. Veins (Figure 42.13)a. Valves are open