LECTURE 7: Nutrition Among Animals

• Herbivores feed on plants.
• Carnivores feed on other animals.
• Omnivores feed on both plant and animals.
• Saprophagus feed on decaying organic matters and are decomposers.
• Plankton is a micro organism carried by tides.
• Organic debris is from disintegrating remains of plants and animals.
• Suspension feeding is catching and ingesting food particles suspended in water.
• Suspension feeding may have ciliated surface generate water currents to draw food particle in suspension.
• Suspension feeding may use mucuos sheets to direct food to digestive tract.
• cilia on edges of tentacles draw water between pinnules to trap food particles in mucus.
• thoracic appendages trap plankton or organic particles.
• Baleen/whalebone is used to filter plankton.
• Gill rakers strain plankton.
• Deposit feeding exploits disintegrated organic material or detritus that settled at the bottom.
• Deposit feeders pass substrates through their bodies and remove from these whatever nourishment present.
• Feed on food masses are predators as they must locate, capture, hold and swallow prey.
• Invertebrates has:

  • no true teeth
  • w/ beak and toothlike structures for biting and holding.
• Fish, amphibians, reptiles uses teeth to grip and swallow whole prey.
• Mammals are the only group w/ true mastication or chewing capacity.
• Feed on fluids are mostly parasites.
• Animal digestion is the physical and chemical breakdown of food into smaller units for absorption.
• Carbohydrates are simple sugar.
• Proteins are amino acids.
• Lipids are fatty acids.
• Animal digestion can be intercellular and extracellular.
• Extracellular digestions resolves the limitation of intracellular through evolution of alimentary system.
• Intracellular digestion is when food particle taken inside food vacuole through phagocytosis.
• Porifera uses intracellular digestio ( filtration and phagocytosis)
• Cnidaria traps food particles and digests food in gastrovascular cavity.
• In platyhelminthes, trematodes ingest food.
• In platyhelminthes, cestodes absorb food through tegument.
• Nematoda has complete digestive tract.
• Mollusca, gastropods feed on plants and algae.
• In mollusca, bivalves are filter feeders.
• Cephalopods feed on small invertebrates.
• Arthropoda is diverse feeding.
• In echinodermata, carnivorous sea star feed on bivalves.
• Basket star are filter feeder.
• Sea cucumber are bottom feeder.
• Cephalochordate feed on small organism in water.