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Animal Nutrition III (Ch. 41). Ruminant digestion Symbiosis Definition Algal-invertebrate Chemoautotroph-invertebrate. Hydrothermal vent H 2 S (sulfide) chemoautotrophy. Keywords. Basic parts of alimentary canal. Mechanical digestion. storage. absorption. mouth. anus.
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Ruminant digestion Symbiosis Definition Algal-invertebrate Chemoautotroph-invertebrate Hydrothermal vent H2S (sulfide) chemoautotrophy Keywords
Basic parts of alimentary canal Mechanical digestion storage absorption mouth anus
Cecum • Allows breakdown of cellulose in herbivores • One opening and exit - lower oxygen, slower passage • Digested cellulose must be reintroduced to digestive system
Ruminant 4 chambered stomach • Rumen and reticulum - where symbiotic bacteria and protists break down cellulose • Cow rechews food • Omasum - where water is absorbed • Abomasum - further digestion by cow’s enzymes
Autotroph-invertebrate symbiosis • Symbionts are algae • Algae photosynthesize and provide molecules such as sugars to the host • Hydra, anemones, giant clams, corals
Chemoautotroph-invertebrate symbiosis • Symbionts are chemoautotrophic bacteria • Bacteria use hydrogen sulfide as an energy source and provide molecules such as sugars to host • Tubeworms, clams, mussels
Life at a vent O2 H2S
Respiratory surface of tubeworm H2S O2 Hb
Chemoautotrophy: Bacteria oxidize sulfide and use the energy for carbon fixation H2S + O2 SO4= ATP carbohydrate ADP Calvin-Benson Cycle CO2