Organismal Bio. II

• Fungi get their energy by decomposing organic matter, humans get energy through food, and plants obtain energy through photosynthesis
• Nutrition


  Process of providing or obtaining food necessary for the health, survival, and growth of an organism
• Processes of nutrition in animals

  1. Ingestion (chewing and swallowing of food in the mouth)

  2. Digestion (partial digestion in the stomach, further digestion in the small intestine)

  3. Absorption (nutrients pass through the lining of the small intestine to the blood)

  4. Assimilation (the cell uses the nutrients incorporated into it)

  5. Egestion (removal of waste products of digestion)
• Defecation


  Process used to remove the fecal matter from the body, excretion of waste products
• Nutrients


  Substances that provide energy for the organism's metabolic processes such as growth, maintenance, reproduction, and immunity
• Nutrients that provide energy

  • Carbohydrates
  • Proteins
  • Fats/Lipids
• Calories


  Measure of energy in food, humans need about 2000-2500 kilocalories per day
• Types of organisms according to nutrition

  • Autotrophic
  • Heterotrophic
• Autotrophic organisms


  • Can produce their own food
• Types of autotrophic organisms

  • Photoautotrophic (use sunlight, e.g. green algae, cyanobacteria, plants)
  • Chemoautotrophic (use chemical energy, e.g. bacteria that live in soil using nitrogen, organisms in volcanic vents or under the ocean using sulfur)
• Heterotrophic organisms


  • Cannot produce their own food
• Types of heterotrophic organisms

  • Saprophytic (decomposers, obtain nutrients from dead organic matter, e.g. fungi, bacteria)
  • Parasitic (parasite takes food from host, harming the host, e.g. lice, ticks, mosquitoes, tapeworms, roundworms, hookworms)
  • Holozoic (ingest solid or liquid food, digest and absorb it, e.g. humans, animals)
• Types of holozoic organisms

  • Herbivores (diet consists of plants, have flat teeth)
  • Carnivores (diet consists of animals, have canine teeth)
  • Omnivores (diet consists of both plants and animals, have both flat and canine teeth)