Biochemistry

  1. All organic molecules contain the element carbon which can make four strong covalent bonds. Energy is often stored in these bonds.

  2. Organic macromolecules are made of simple units called monomers which are put together to make large molecules with many units called polymers

  3. These units are joined by the process of dehydration synthesis and taken apart by the process of hydrolysis.

  4. Monomer of a carbohydrate: monosaccharide

  5. Monomer of a protein: amino acid

  6. Monomer of a nucleic acid: nucleotide

  7. “Monomers” of the lipid triglyceride: glycerol and fatty acids

  8. Nucleotides consist of: 5-carbon sugar, base, phosphate group 

  9. What are the functions of carbohydrates? 

monosaccharide: quick energy  poly: energy storage or structure

  1. List 2 polysaccharides that are used for energy storage and two that are used for structure. 

  1. energy storage: starch, glycogen

  2. structure: cellulose, chitin

  1. What are the functions of lipids? long-term energy storage

  2. What are functions of nucleic acids? Genetics, instructions for making proteins

  3. What are the functions of proteins? catalysts (enzymes), structure (hair), immunity (antibodies), etc.

  4. Which organic compound is the main source of energy for living things? carbohydrates

  5. What kind of macromolecules are enzymes? protein

  6. Enzymes must be folded correctly to be functional. A correctly folded enzyme has an active site which is where the reactants (called substrates attach. 

  7. Enzymes affect the reactions in living cells by increasing/decreasing the rate of the reaction. They do this by decreasing the activation energy needed to start a reaction.

  8. What are two major factors that affect the rate of an enzymatic reaction?

pH, temperature (also concentration of substrate and product)

  1. Circle the products and underline the reactant(s) in the chemical reaction: 

(reactants) CO2 + H2O→ H2CO3 (products  )

  1. What is the term used to describe the energy needed to get a reaction started? activation energy

  2. Define exergonic reaction: chemical reaction in which energy is released (products have less energy than the reactants) may start on its own



  1. Define endergonic reaction: chemical reaction in which energy is absorbed (products have more energy than the reactants) energy must be supplied; will not start on its own.

  2. Define the primary structure of a protein. What bonds are involved in this structure?  chain of amino acids in a specific order; peptide bonds

  3. Define secondary structure of a protein. What bonds are involved in this structure?  alpha-helix or beta-pleated sheet; hydrogen bonds (involves the backbone)

  4. Define tertiary structure of a protein. What bonds are involved in this structure?  globular, 3D; bonds: hydrogen, ionic, covalent (disulfide bridges), van der Waals. Also polar amino acids on outside (next to water) and nonpolar amino acids on the inside (away from water).

  5. Define quaternary structure of a protein. What bonds are involved in this structure?  two or more tertiary proteins (polypeptides now called subunits)

  6. The function of a protein is dependent on its shape

  7. From its name you know that protease is an enzyme. You can also infer that it will break down protein.  

  8. Identify the following structures: monosaccharide, lipid (triglyceride), nucleotide, amino acid; long chain is a polypeptide or protein (see the nitrogen (N)?)



















  1. How does a change in pH above or below optimal pH affect enzyme function? Why? Decreases function. The hydrogen and/or hydroxide ions will interfere with ionic bonds of the enzyme’s tertiary structure and cause the enzyme to unfold or “denature.” If the active site unfolds, the enzyme will not function.

  2. How does temperature above optimal temperature affect the reaction rate of an enzyme? Why? decreases rate. The increased molecular motion would disrupt hydrogen bonds of the enzyme’s tertiary structure and cause the enzyme to unfold or “denature.” If the active site unfolds, the enzyme will not function.

  3. How does temperature below optimal temperature affect the reaction rate of an enzyme? Why? decreases rate. Decreased molecular motion results in slower reaction rate