Biology (Unit 4)

• Fluid within cells


  Mixture of molecules and ions
• Types of molecules in cell fluid


  • Simple and inorganic (water, phosphates, hydrogen ions, sodium ions)
  • Organic (contain carbons, hydrogens, with some oxygen, sulfur, or nitrogen)
• Macromolecule


  Organic molecules that combine to create a larger molecule, also called a nutrient
• Major categories of macromolecules


  • Carbohydrates
  • Lipids (Fats)
  • Proteins
  • Nucleic Acids
• Carbohydrates


  • Contains carbon, hydrogen, oxygen
  • Very consistent ratio of two hydrogens : one carbon : one oxygen
  • Provides a "quick" dose of energy
• Types of carbohydrates


  • Monosaccharides (a sugar with 3-7 carbon atoms)
  • Disaccharides (a sugar composed of two monosaccharides)
  • Polysaccharides (a large molecule composed of many monosaccharides linked together)
• Lipids


  • Known for being insoluble in water
  • Contains an alcohol group (glycerol) and three tails of carbon and hydrogen atoms (fatty acid chains)
  • Used for storing a lot of energy and forming the layers that separate inside vs outside of cells (phospholipid bilayer)
• Proteins


  • Have a wide variety of functions within the body (supports cell activity, aids muscle movement)
  • Made up from a series of amino-acids, joined together by a peptide bond (chains = polypeptides)
• Enzyme


  Protein molecule that breaks down the four different macromolecules using water through a process called hydrolysis
• Enzymes have an "ase" at the end, e.g. Lipase will break down the lipid macromolecule
• Digestive enzymes will speed up the hydrolysis needed to break down macromolecules
• Minerals and vitamins are both organic and inorganic, aiding in many cellular and body functions by enabling chemical reactions to occur
• Water


  • Important for flushing toxins, lubricating tissues and joints, transporting nutrients, regulating body temperature
• macromolecules are broken down by the body and used for energy through a process called metabolism
• Trophs


  Types of ways in which plants obtain food
• Types of Trophs


  • Autotrophs
  • Heterotrophs
• Autotrophs


  Obtain energy by making their own food
• Heterotrophs


  Cannot make their own food
• Types of Feeders


  • Filter Feeder
  • Substrate Feeder
  • Fluid Feeder
  • Bulk Feeder
• Filter Feeder


  • Almost always an aquatic animal
  • Will draw water into its mouth and filter any small organisms that can be digested

  
• Filter Feeder


  • Tube sponge
  • Baleen Whale
• Substrate Feeder


  • Will live in or on the food they eat
  • Move by eating through the substrate
• Substrate Feeder


  • Earthworms eating dirt in the ground
  • Caterpillars eating leaves

  
• Fluid Feeder


  • Obtain their food by sucking nutrient-rich fluid from live plants or animals
  • There are no real solid objects that are ingested
• Fluid Feeder


  • Hummingbirds will suck nectars out of flowers
  • Mosquitoes suck blood

  
• Bulk Feeder


  • Most vertebrates use this method
  • Will consume their food in large portions, sometimes using a claw or teeth to tear pieces of meat or vegetation
• The "mouth" of these feeders will vary depending on their feeding method
• Stages of Food Processing


  1. Ingestion

  2. Digestion

  3. Absorption

  4. Elimination
• Ingestion


  The taking in or eating of food
• Digestion


  The food gets broken down through mechanical and chemical processes, in order to reduce the food to small molecules for the cells to absorb
• Absorption


  The food sub-units gets transported from the digestive system to the circulatory system, where it can be distributed throughout the body
• Elimination


  The removal of food waste that was not digested
• Alimentary Canal


  • It is a tube that has a mouth end to take in food, and an anus to eliminate food
  • The digestive tract that composes the digestive system
• Types of Digestion

  • Mechanical Digestion
  • Chemical Digestion
• Mechanical Digestion


  The physical breakdown of food into smaller pieces through the use of teeth or beaks, alongside the contractions and churning motions within the stomach
• Chemical Digestion


  The breakdown of food macromolecules into smaller molecules through the use of enzymes
• Digestive System


  The system responsible for breaking down food and absorbing nutrients
• General Diagram


  • Overview to help with our memory
• Salivary Glands


  Specialized tissue that secretes/releases saliva into our mouth
• Saliva


  • Starts chemical digestion with the enzyme amylase
  • Dissolves soluble food particles
  • Lubricates and makes insoluble food easier to swallow
  • Activates taste buds