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Nutrition in Heterotrophs

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Nutrition in Heterotrophs Nutrition in Heterotrophs Required Nutrients Water Carbohydrates Lipids Proteins Minerals Vitamins Water Makes up ~90% of some animals Makes up a major portion of many body parts Humans require at least 1 L / day Carbohydrates Main source of energy High in bulk fiber Refined carbohydrates do not supply need Obesity American consumption ~2 lb refined sugar/week Lipids Parts of membranes Energy reserves Essential fatty acids (olive oil, canola oil) Saturated fats Roughly 40% of American diet Proteins Consist of amino acids hooked together aa-aa-aa-aa-aa-aa-aa-… 20 amino acids 8 essential amino acids Animal protein contains all 20 amino acids Vegetables do not contain required balance of amino acids for humans Vegetarian diet a vegetable does not provide complete protein Complementarities can supply all essential amino acids. Beans supply – lysine corn supply – methionine Fig. 41.4 Minerals 17 essential minerals Inorganic substances: Iron, iodine, zinc, calcium, sulfur, potassium, chloride, magnesium, etc. Required for growth, metabolism, survival Deficiencies – stunted growth or weak Vitamins 13 essential vitamins Complex organic compounds Play metabolic role – cofactors and coenzymes Animals cannot synthesize themselves Vitamins Water Soluble vitamins Taken in excess – eliminated in urine generally do no harm C B complex (B1, B2, B6, B12, niacin) Fat Soluble vitamins Taken in excess – stored in fatty tissues can cause serious health problems A D E K Water Soluble Vitamins Need Source Too Little Too Much C collagen synth., Fruits and Scurvy, poor diarrhea, inhibits free vegetables healing, digestive radicals, builds impaired upsets bone, & teeth immunity B Coenzyme action meat, Varies None in most complex green leafy Niacin - skin vegetables, flushing whole grains B6 –impaired coordination nervous function, Meat, dairy, Anemia, non– toxic B12 coenzyme in yeast impaired nucleic acid vegan diet - nerve metabolism limited function Fat Soluble Vitamins Need Source Too little Too much A Vision, bone, Beta carotene- night skin changes, teeth yellow or green blindness, vomiting, leafy vegetables dry skin, bone & liver poor damage immunity D Bone growth; Formed in skin, bone retarded growth, mineralization fortified milk, deformities kidney damage Ca absorption yolks (Rickets) E counters free Whole grains, anemia, muscle weakness, radicals, dark-green leafy nerve fatigue, maintains cell vegetables, damage headaches, membranes vegetable oil nausea K Blood clotting, Enterobacteria, Hemorrhage jaundice, liver ATP formation Leafy damage, anemia vegetables Simple Digestive Processes 1. Intracellular Digestion Amoeba Paramecium Phagocytosis Simple Digestive Processes 2. Extracellular Digestion carbohydrates simple sugar proteins amino acids lipids glycerol & fatty acids Digestive Systems 1. Incomplete digestive system - Gastrovascular Cavity Hydra Tentacles Mouth Phagocytosis – Intracellular Digestion Extracellular Digestion Gastrovascular Cavity Incomplete Digestive System Planaria 2. Complete Digestive System “ a tube within a tube construction” Mouth Pharynx Esophagus Crop/gizzard Stomach Intestine Anus Annelids – Segmented Worms Complete Digestive System Mollusks Roundworms Digestive System Functions 1. Mechanical Processing – breakdown, mixing, and food movement 2. Secretion – release of digestive enzymes that aid digestion 3. Digestion – breakdown of food particles 4. Absorption – passage of digested nutrients and fluid from the tube (extracellular space) into the body’s cells 5. Elimination – explusion of undigested materials Bird Specializations Arthropods BirdGizzard Specializations Stomach Chordates - birds Ruminant Specializations Vertebrate Mouth Specializations Teeth Specialization Incisors Canines Molars Carnivore Herbivore: Teeth Specialization Incisors Molars Rodent – Gnawing Grazing Circulatory Systems Single-celled organisms O2 & Food CO2 & Waste Circulatory Systems Rapidly transports substances to and from cells May carry gases, food, chemical messages, waste material and living cells Interstitial fluid bathes tissues Heart – muscular blood vessel that acts as a pump 1. Open Circulatory Systems Open Circulatory System Snails Open Circulatory System Land Arthropods 2. Closed Circulatory System Fish – 2 chambered heart 1 ventricle 1 atrium Amphibians – 3-chambered heart 1 ventricle 2 atria Birds and Mammals – 4-chambered heart 2 ventricles 2 atria Atrium – thin-walled; receives blood from body; pumps to ventricle Ventricle – muscular wall; forces blood into major arteries Cellular Respiration C6H12O6 + O2 CO2 + H2O + energy Respiration in Water and Air aquatic environments terrestrial environments Animal Gas Exchange Protists – direct diffusion of gases Gas Exchange – surface exchange vascular exchange Gas Exchange – surface/vascular exchange Earthworms Gas Exchange - Gills Gas Exchange - Lungs Gas Exchange - Trachea Terrestrial Insects Gills Fish Gill Filament Countercurrent Exchange Gas Exchange – Lungs Amphibians Gas Exchange – Birds Air Flow 34% efficient, no air mixing Gas Exchange – Human .
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