2 15 Biology Notes Respiration What do you need for gas exchange at the cellular level Wet cell membrane the gases must be in a liquid solution Sufficient surface area exchange is by diffusion Thin membrane only a few cell layers thick Do small aquatic organisms need special structures No surface area volume ratio great Do large aquatic organisms ness special structures Yes surface area volume ratio problem Do small terrestrial organisms need special structures depends on the environments around them so yes and no Do large terrestrial organisms need special structures Yes fighting ratio and water loss problem What adaptations have organisms developed to deal with these problems Terrestrial plants Waxy substance on leaves prevents water loss and all gas exchange so have small holes openings Stomata on leaves with guard cells to allow gas exchange A leaf is not solid spongy mesophyll Exchange surface is internal Fig 43 6 43 22 Large Aquatic organisms Large thin respiratory surface gills Integration with circulatory system Respiratory pigments hemoglobin in blood Fig E33 2 Large and small Terrestrial organisms Internal respiratory surface Integration with circulatory system Respiratory Pigments hemoglobin in blood Animals have openings to their respiratory system 1 opening Insects have openings to their respiratory system many Lungs small amount mainly one opening close to circulatory system vs Spiracles many different openings not close to circulatory system Steps in Human Respiration not a determined starting place all work together A Diffusion of oxygen out of the capillaries 4 B Diffusion of carbon dioxide out of the capillaries 2 6 C Diffusion of oxygen into the capillaries 2 6 D Inhalation of air 1 E Diffusion of carbon dioxide into the capillaries 4 F Transport of blood from the lungs 3 G Transport of blood to the lungs 5 H Exhalation of air 7
View Full Document