Animal Nutrition
Herbivore: eat plants
Carnivore: eat other animals
Omnivore: eat plants and animals
Nutrient: substance in food needed for growth, maintenance, repair
Macronutrients: 3 major nutrients that make up bulk of ingested food (carb, protein, lipid)
Micronutrient: 2 nutrients required but in smaller amounts (vitamins, minerals)
Carbohydrate role: used by cells to make ATP during respiration Ex: glucose
Excess glucose makes: glycogen or fat
Neurons die without: glucose
Lipids role: protection, insulation, fuel storage
Phospholipids: in myelin sheath and cell membranes
Cholesterol: stabilizes membrane
Prostaglandins: smooth muscle contraction, BP control, inflammation
Proteins role: make up building blocks/structural materials, functional molecules
Protein examples as building block: keratin, collagen, elastin, muscle
Protein examples as functional molecule: enzymes and hormones
Essential nutrients: required by cells and must be obtained from diet
Essential Amino Acid: essential nutrient, must get from food in preassembled form, ½ of total amino acids (10/20)
Insufficient amino acids: protein deficiency (malnutrition)
“Complete” proteins: meat, eggs, cheese (all essential AA)
Essential Fatty Acids: certain unsaturated fatty acids that must be in diet, make up lipids, wide range of application in body
Example of Essential Fatty Acid: linoleic and linolenic acid (oils)
Vitamins: organic compound that helps body use nutrients, most are coenzymes and must be ingested, 13 total
Vitamin made in skin, not ingested: D
Vitamin made by intestinal bacteria: B and K
Vitamin converted from Beta-carotene: A
Water soluble Vitamins: B and C
Fat-soluble: A, D, E, K
Antioxidants: neutralize free radicals, Vitamins C, E, A and mineral selenium
Minerals: simple inorganic nutrients, 7 required in moderate: Calcium, phosphorus, potassium, sulfur, sodium, chlorine, magnesium (others in trace)
Harden bones: calcium, phosphorus, magnesium
Oxygen binding to hemoglobin: iron
Thyroid hormone synthesis: iodine
Major electrolytes in blood: sodium and chlorine
Epidemiology: study of human health/disease
Undernourishment: diet with less chemical energy than needed
Malnourishment: long-term absence of 1+ essential nutrients from diet, deformities, disease, death
Ingestion: act of eating
Suspension feeders: eat food from water (sponge, whale)
Substrate feeders: live in or on food source (caterpillar)
Fluid feeders: suck nutrient rich fluid from host (mosquito)
Bulk feeders: eat large pieces of food (human)
Propulsion: movement of food in GI tract (swallowing and peristalsis)
Peristalsis: propulsion of food with rhythmic contraction and relaxation
Mechanical breakdown/digestion: chewing, food with saliva, food churning in stomach, segmentation
Segmentation: local constriction of intestine that mixes food with digestive juices
Chemical digestion: catabolic steps with enzymes breaking down complex food into chemical building blocks
Enzymatic hydrolysis: splitting molecules with addition of water
Absorption: passage of digested fragments from lumen of GI tract into blood or lymph
Defecation: elimination of indigestible substance via anus
Intracellular digestion: food is engulfed by endocytosis and digested in food vacuole
Extracellular digestion: breakdown of food particles outside the cells
Gastrovascular cavity: in simple body animals and does digestion and distribution
Complete Digestive Tract: complex animals with digestive tubs from mouth to anus (alimentary canal, GI tract)
Mammalian accessory glands: salivary glands, pancreas, liver, gallbladder
Sphincters: valves that regulate movement between compartments
First stage of digestion: mechanical in the oral cavity
Second stage of digestion: salivary glands and amylase
Salivary glands: deliver saliva and lubricate food
Amylase: enzyme, initiates breakdown of glucose and starch
Bolus: circle food shaped by tongue
Esophagus: takes food from mouth down to stomach, peristalsis
Stomach: stores food and secretes gastric juice
Gastric juice: made of HCL and pepsin, converts meal to acid chime
Parietal cell: secrete H+ and Cl- separate
Chief cells: secrete inactive pepsinogen
Mucin cells: secrete mucus
Pepsinogen: activated to pepsin when mixed with HCL
Intrinsic factor: secreted by parietal cell for absorption of vitamin B12 in small intestine
To mature red blood cells need: vitamin B12
Pancreas: solution is alkaline and neutralizes acidic chyme
Liver: produces bile
Bile: aids in digestion and absorption of fat, yellow-green alkaline solution with bile salts and bilirubin
Bile salts: cholesterol derivatives
Bilirubin: pigment formed from heme after breakdown of old RBCs
Small intestine: longest section of GI tract, major organ of digestion and absorption
3 parts of small intestine: Duodenum, Jejunum, Ileum
Duodenum: acid chyme mixes from stomach with digestive juices from pancreas, liver, gallbladder, small intestine
Villi and microvilli: absorb nutrients in the small intestine, line the walls
Hepatic portal vein: delivers nutrient rich blood to the liver and to the heart
Large intestine: cecum, appendix, colon, rectum
Cecum: first part of large intestine. aids in fermentation of plant material
Appendix: lymphoid tissue and bacterial storehouse recolonizing gut when necessary, immunity
Colon oder: Ascending, Transverse, Descending, Sigmoid
Rectum: feces pass through to anus
Colon function: recover vitamin, water, electrolytes
Bacterial flora: 1000+ bacteria types
Bacterial flora functions: ferments ingestible carbs/mucin, synthesize B complex/vitamin K, suppress pathogenic bacteria
Ruminants: elaborate adaptation for herbivorous diet, 4 compartments instead of 1, cow
Longer cecum: herbivores to digest vegetation
Excess calories are stored as: glycogen in liver/muscles and fat in adipose tissue
Overnourishment: causes obesity, excessive intake of food stored as fat
Obesity causes: diabetes (type II), colon/breast cancer, heart attack, stroke
Leptin: create feeling of being full