Biological Molecules

• What are monomers?


  Smaller units that can create larger molecules
• What are polymers?


  Large molecules made from many monomers bonded together
• Name three examples of monomers.


  Glucose, amino acids, nucleotides
• What is a condensation reaction?


  A reaction that joins two molecules together and removes water
• What is hydrolysis?


  A reaction that breaks apart monomers using water
• What are the three levels of carbohydrate size?

  • Monosaccharides: one sugar unit
  • Disaccharides: two sugar units
  • Polysaccharides: many sugar units
• Name three examples of monosaccharides.


  Glucose, fructose, galactose
• What are the three disaccharides you need to know?

  Sucrose, maltose, lactose
• What is the structure of alpha glucose?


  Hydrogen atom on top and hydroxyl group on the bottom at carbon one
• How does beta glucose differ from alpha glucose?


  The hydroxyl group is on top and the hydrogen atom is on the bottom at carbon one
• What type of bond forms between two monosaccharides in a disaccharide?


  A glycosidic bond
• What is the word equation for maltose formation?

  Glucose + Glucose
• What is the word equation for sucrose formation?

  Glucose + Fructose
• What is the function of starch in plants?


  It serves as a store of glucose for chemical energy
• What is the function of cellulose in plants?


  It provides structural strength in the cell wall
• What is the function of glycogen in animals?


  It serves as a store of glucose, mainly in the liver and muscle cells
• What is the difference between starch and cellulose in terms of glucose isomers?


  Starch and glycogen are made from alpha glucose, while cellulose is made from beta glucose
• What does a 1 to 4 glycosidic bond refer to?


  The bond forms between carbon one in one molecule and carbon four in another
• What is amylose?


  An unbranched polymer that coils to form a helix
• What is amylopectin?


  A branched polymer that has both 1 to 4 and 1 to 6 glycosidic bonds
• Why are polysaccharides insoluble?


  Because they are large and do not affect the water potential of the cell
• What is the structure of cellulose?


  Long straight chains formed by 1 to 4 glycosidic bonds
• What is the role of hydrogen bonds in cellulose?


  They join parallel chains together to provide strength
• How does glycogen differ from starch?

  Glycogen has a higher proportion of 1 to 6 glycosidic bonds, making it more branched
• What are the two types of lipids you need to know?

  • Triglycerides
  • Phospholipids
• What is the structure of a triglyceride?


  One glycerol molecule and three fatty acid chains
• How are triglycerides formed?


  Through three condensation reactions with the loss of three water molecules
• What type of bond forms in triglycerides?


  An ester bond
• What is the difference between saturated and unsaturated fatty acids?


  Saturated fatty acids have no double bonds, while unsaturated have at least one double bond
• What is the function of triglycerides?


  They serve as an energy store
• How do triglycerides affect water potential?


  They do not affect water potential due to being large and hydrophobic
• What is the structure of phospholipids?


  One glycerol, two fatty acid chains, and one phosphate group
• How do phospholipids behave in water?


  The hydrophilic heads attract water while the hydrophobic tails repel it
• What is the general structure of an amino acid?


  A central carbon, an amino group, a carboxyl group, a hydrogen atom, and a variable R group
• What is a dipeptide?


  A molecule formed by two amino acids bonded together
• What is the primary structure of a protein?


  The order or sequence of amino acids in a polypeptide chain
• What is the secondary structure of a protein?


  The folding or twisting of the primary structure, forming alpha helices or beta pleated sheets
• What holds the secondary structure of a protein in place?


  Hydrogen bonds
• What is the tertiary structure of a protein?


  The unique 3D shape formed by further folding of the secondary structure
• What bonds stabilize the tertiary structure of a protein?


  Ionic, hydrogen, and sometimes disulfide bonds