Biology

• Nutrition


  Any substance required for the growth and maintenance of an organism
• Types of organism


  • Autotrophs
  • Heterotrophs
• Autotrophs


  • Organisms that obtain energy from sunlight & chemicals to produce their own food
  • "self feeding"
  • Producers
• Photosynthesis (Phototrophs)


  Uses energy derived from sunlight to produce organic molecules from CO2 and H2O

  Ex. All green plants
• Chemosynthesis (Chemo-autotrophs)


  Uses energy derived from the oxidation of substances to synthesize organic compounds

  Ex. Sulfuric bacteria oxidize sulfur to sulfate
• Heterotrophs


  • Organisms that cannot make their own food & obtain their energy from other organisms
  • "other source feeding"
  • Consumers
  • Ex. Fungi, animals
• Types of heterotrophic nutrition

  • Saprotrophic Nutrition
  • Parasitic Nutrition
  • Holozoic Nutrition
• Saprotrophic Nutrition


  • Yeast, mushrooms
• Parasitic Nutrition


  • Tapeworm, lice
• Holozoic Nutrition


  • Human being, amoeba
• Plant Nutritional Requirements


  • Water
  • Carbon dioxide
  • Essential macro & micronutrients/elements
• Plant Specialized Absorptive Structures

  • Root hairs
  • Root nodules (where N-fixing bacteria thrive)
  • Mycorrhizae (a symbiotic interaction between a young root & a fungus)
• Plant Nutritional Adaptations


  • Symbiosis of plants & soil microbes
  • Symbiosis of plants & fungi
  • Parasitism
  • Predation
• Animal Nutritional Requirements


  • Carbohydrates
  • Proteins
  • Fats
  • Essential nutrients (amino acids, fatty acids, vitamins, trace elements)
• Types of Animal Feeding Mechanisms

  • Substrate feeders
  • Filter feeders
  • Fluid feeders
  • Bulk-feeders
• Types of Animal Digestive Compartments

  • Food vacuoles
  • Incomplete digestive tract
  • Complete digestive tract

  
• Types of Animal Feeding

  • Herbivore
  • Carnivore
  • Omnivore
• Feeding Adaptations


  • Suspension-feeders: Sift food from water (e.g. baleen whale)
  • Substrate-feeders: Live in or on their food (e.g. earthworm)
  • Fluid-feeders: Suck fluids from a host (e.g. mosquito)
  • Bulk-feeders: Eat large pieces of food (e.g. most animals)
• Types of Digestive Systems

  • Incomplete Digestive System: One-way, saclike
  • Complete Digestive System: A tube with an opening at each end
• Digestive System


  Performs the mechanical and chemical processes of digestion, absorption of nutrients, and elimination of wastes. Consists of the mouth, esophagus, stomach, intestines, and accessory organs.
• Digestion


  1. Breakdown of food into a smaller, usable form

  2. Ingestion

  3. Peristalsis

  4. Digestion

  5. Absorption

  6. Defecation
• Types of Digestion


  • Mechanical Digestion: Ingested food is physically broken down into smaller pieces by chewing or mastication and peristalsis
  • Chemical Digestion: Food is acted upon by catalytic enzymes to be broken down into its absorbable forms
• Parts of the Digestive System

  • Digestive tract: Mouth, Pharynx, Esophagus, Stomach, Small intestine, Large intestine, Anus
  • Accessory organs: Teeth, Tongue, Salivary glands, Liver, Gall bladder, Pancreas

  
• Oral/Buccal Cavity or Mouth


  Taste, Mechanical breakdown of food, Chemical digestion of carbohydrates, Ptyalin or salivary amylase in the saliva secreted by 3 pairs of salivary glands
• Teeth


  • For mechanical digestion thru biting, grinding, cutting, chewing
• Tongue and Salivary Glands


  Food manipulation, taste, and speech, 3 pairs of Salivary Glands: Parotid, Sublingual, Submandibular Glands, Saliva(99.5% H2O) lubricates food and begins digestion
• Pharynx


  Common passageway for food and air, where swallowing begins
• Esophagus


  25 cm or 10 inches long, secrete mucus, transport food thru peristalsis, (Upper Esophageal Sphincter & Lower Esophageal Sphincter), Peristalsis - smooth muscle contractions propel food thru a sphincter
• Stomach


  Mixes & stores ingested food with HCl into chyme, chemical and mechanical breakdown of food, Secretes hydrochloric acid & digestive juices that break down proteins and fats and may kill bacteria, Peristalsis
• Small Intestines


  Where most enzymatic hydrolysis of macromolecules from food occurs and absorption of digested food by its villi, 6 meters divided into: duodenum - 25cm/10in; complete digestion of food by enzymes, jejunum - 8 ft; absorb H2O & products of digestion into bloodstream, ileum - 12 ft; absorption of end products, with villi & microvilli
• Large Intestine/Colon


  Concentrates & stores undigested matter by absorbing Na, Vit K & water, Doesn't have villi or coils, Many bacteria live, thrive & process undigested material into feces, 1 meter long, Cecum - pouch-like area, Colon - ascending, transverse, descending, sigmoid; with haustrae = pouches, Rectum - a short extension of the large intestine, where compacted undigested food from the colon is pushed via peristalsis, Distention triggers expulsion of feces
• Pancreas


  Functions: acini - secrete digestive enzymes that break down all major food molecules, Islets of Langerhans or pancreatic islets - secrete insulin and glucagon that control glucose metabolism
• Liver and Gall Bladder

  The liver produces bile salts that emulsify fats and bile is stored in the gall bladder
• The Urinary System


  A vital biological system that removes excess and waste products from the body to maintain homeostasis

  most of these products are in fact used and broken down components of metabolism that leave the body in the form of urine, sweat, or feces.
• Components of the Excretory System

  • Two kidneys
  • Two ureters
  • Urinary bladder
  • Single urethra

  
• Functions of the Urinary System

  • Excretion
  • Regulation of blood volume and pressure
  • Regulation of the concentration of solutes in the blood
  • Regulation of extracellular fluid pH
  • Regulation of RBC synthesis
  • Vitamin D synthesis

  
• Kidneys


  • Are bean-shaped
  • About the size of a tightly clenched fist
  • Located in the abdominal cavity, with the right kidney just below the liver and the left kidney below the spleen

  
• Ureters

  • Extend from the kidneys to the urinary bladder within the pelvic cavity

  
• Adrenal glands


  • Located at the superior pole of each kidney

  
• Kidneys


  • Located behind the parietal peritoneum
  • Fat surrounds each kidney
  • Renal arteries extend from the abdominal aorta to each kidney, and the renal veins extend from the kidneys to the inferior vena cava
  • Renal Capsule – a layer of fibrous connective tissue surrounding each kidney
  • Renal fascia – a thin layer of connective tissue surrounding the fat, helping anchor the kidneys and fat to the abdominal wall
  • Hilum – a small area where the renal artery and nerves enter