fluid and caval rupture Solve 3 ways 1 Empty lungs before diving 2 Cut off

Fluid and caval rupture solve 3 ways 1 empty lungs

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fluid, and caval rupture - Solve 3 ways: 1. Empty lungs before diving 2. Cut off blood entirely to lungs (No circulation) 3. Lungs collapse - Dolphins have hinged ribs and lungs not firmly attached so they can “squish” - Turtles don’t have a collapsible chest, so they swim shallow, but leatherbacks may have a flexible shell - Sinuses lined with bone (vascular rete): nothing to collapse with a bony covering, but can fill with blood supply, vessels swell with H2O and equalize the pressure, so the bones don’t crush - Air must go somewhere: it is stored in airways (bronchioles and trachea), air under pressure wont go into the bloodstream, cant be crushed under pressure because they have flexible cartilage rings in airways reinforced airways increase tidal flow without collapse High Pressure Nervous Syndrome - Pressure affects neural transmission, leading to transmission errors and misfunctioning of brain stem
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EXAM 3 REVIEW Metabolism - The sum of all chemical reactions in all cells - Anabolism + Catabolism Metabolic Rate - Energy expenditure/time (kcal/hr) - MR = aW b a = MR/unit mass, W = body mass, b = slope - Measured in 3 ways: 1. Calculate change in energy in vs out 2. Determine total heat output of animal (calories in vs out) 3. Measure O2 consumption (because O2 is final electron acceptor) - Basal Metabolic Rate (endotherms): MR at physical rest, several hours after eating, in the thermoneutral zone (TNZ = room temp) - Standard Metabolic Rate (ectotherms): MR adjusted by environmental temps, varies - BMR and SMR increase when thyroid hormones increase Specific Dynamic Action (SDA) - Diet-induced thermogenesis (DIT) - An increase in MR above BMR/SMR levels after food intake - Lasts days for ectotherms and hours for endotherms Temperature Largely Effects Metabolism - Increased temps denature enzymes - Homeotherms: have one usual set internal temperature (stable) - Endotherms: produce their own heat - Vasoconstrict @ skin temp=environmental temp - Vasodilate @ skin temp between core-environment temps - Poikilotherms: alternate internal temps, compensate by changing enzyme [ ] , homeo-viscous membrane, and pH regulation - Ectotherms: get heat from environment - Membranes o @ low temps = high viscosity and rigid (low saturation) o @ high temps = low viscosity and fluid (high saturation) SA:V Ratios - SA related to squared, volume related to cubed - Small animals have a greater SA:V ratio - Heat is produces as a function of Volume - Heat is lost as a function of SA (by skin) - Increased MR = decreased mass/body size = decreased muscular activity (small size = high MR)
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EXAM 3 REVIEW Specific O2 Consumption: MR/gram tissue Heat Production 1. Basal MR (endotherms) o thyroid regulates # of Na/K pumps 2. Sympathetic Nervous stimulation o Non-shivering thermogenesis of Brown Adipose Tissue (BAT): Cold temp or diet stimulate a nerve to release Norepinephrine, thermogenin opens and allows H+ to pass through inner mitochondrial membrane = dissipates H+ gradient as heat without making ATP o Ghrelin may suppress BAT 3. Thyroxine (Hormones) o Increased when cold (hypothyroid), lowers MR 4. Shivering (Muscular activity) 5. SDA/DIT (Digestion) 6.
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