Pathway of Negative Feedback of Fundamentals of Physiology - Notes | BMS 360, Study notes of Biology

Download Pathway of Negative Feedback of Fundamentals of Physiology - Notes | BMS 360 and more Study notes Biology in PDF only on Docsity! 18 January Stimulus → Receptor → Afferent pathway → Integrating center → Efferent pathway → Effector → Response If response is opposite to stimulus – negative feedback System can be anticipatory (neurons sense lowered temperature, start response before core body temp actually lowers) Childbirth example of positive feedback Body water 2/3 intracellular fluid 80% extracellular is in interstitial fluid 20% extracellular is in plasma H2O Molecular weight – 18 daltons Velocity – 1,500 mph Glucose Molecular weight – 360 daltons Velocity – 510 mph Diffusion – random movement Molecules change direction as they hit others Downhill [High] → [low] High temp → molecules move faster → faster diffusion Larger mass → slower diffusion Greater viscosity → slower diffusion Larger surface area → faster diffusion Higher concentration → faster diffusion Net flux – difference between flux in and flux out (fluxin- fluxout) Cells are roughly 10 μm It takes glucose 3.5 sec to diffuse in If they were 10 cm, it would take 11 years Rate of diffusion is proportional to the square of the distance Circulatory system is necessary in a multicellular system for gasses to diffuse into the cell at a reasonable rate Fatty acids Cis is unsaturated Trans is saturated Membrane contains both Aquaporins – pore allowing water to travel in and out of cells