Bio

• The nucleus is the control center of the cell, containing genetic material (DNA) that determines an organism's characteristics.
• Genes are segments of DNA that contain instructions for making specific proteins or determining certain traits.
• Chromosomes are thread-like structures made up of DNA and proteins found inside the nucleus.
• Monomers


  Individual molecules that make up a polymer

  
• Polymers


  Long chains that are composed of many individual monomers that have been bonded together in a repeating pattern
• Condensation Reactions


  Occurs when two molecules combine to form a more complex molecule with the removal of water
• Hydrolysis Reactions


  Occurs when larger molecules are broken down into smaller molecules with the addition of water
• Monosaccharides


  • Glucose
  • Fructose
  • Galactose

  
• Glucose


  A hexose sugar with 2 isomers

  
• Disaccharides


  • Maltose
  • Sucrose
  • Lactose
• Disaccharides


  Sugars that are composed of two monosaccharides joined together in a condensation reaction, forming a glycosidic bond
• Polysaccharides


  • Starch
  • Glycogen
  • Cellulose
• Starch


  The main polysaccharide energy store in plants, composed of amylose and amylopectin which are made of α-glucose
• Glycogen


  The polysaccharide energy store in animals, composed of α-glucose

  
• Cellulose


  A structural component of plant cell walls, composed of long unbranched chains of β-glucose
• Fatty acids


  • Saturated
  • Unsaturated

  
• Saturated fatty acids


  There are no double C=C bonds and the molecule has as many hydrogen atoms as possible

  
• Unsaturated fatty acids


  There is at least one double C=C bond, therefore the molecule contains fewer hydrogen atoms than is maximally possible
• Triglyceride


  Formed by joining one molecule of glycerol to three fatty acids through three condensation reactions, forming ester bonds
• Phospholipids


  Replace one of the fatty acid chains in triglycerides with a phosphate molecule

  
• Amino acids


  The monomer units used to make proteins
• Dipeptides


  Formed when two amino acids are joined together by a condensation reaction, forming a peptide bond
• Polypeptide


  A polymer made of many amino acids joined together by peptide bonds
• Structural levels of proteins


  • Primary
  • Secondary
  • Tertiary
  • Quaternary
• Primary structure


  The specific sequence of amino acids in a polypeptide chain
• Secondary structure


  The curling or folding of the polypeptide chain into α-helices and β-pleated sheets due to the formation of hydrogen bonds
• Tertiary structure


  The overall specific 3-D shape of a protein, which is determined by interactions between R groups and the properties of R groups
• Quaternary structure


  The specific 3-D shape of a protein that is determined by the multiple polypeptide chains and/or prosthetic groups bonded together

  
• Biochemical tests


  • Reducing sugars
  • Starch
  • Non-reducing sugars
  • Proteins
  • Lipids
• Enzymes


  Biological catalysts that speed up the rate of reaction and remain unchanged and reusable at the end of the reaction
• Lock and key model


  Each substrate is a key that only fits a specific lock or enzyme
• Induced fit model


  Alternative model to the lock and key model
• Factors affecting enzyme activity


  • pH
  • Temperature
  • Enzyme concentration
  • Substrate concentration
  • Competitive & non-competitive inhibitor concentration
• DNA


  Stores genetic information
• RNA


  Transfers genetic information and forms ribosomes with proteins
• Differences between DNA and RNA


  • Number of strands
  • Length
  • Pentose sugar
  • Nitrogenous bases
• DNA double helix


  Held together by hydrogen bonds between complementary base pairs
• Semi conservative replication


  The method in which DNA replicates, creating two molecules of DNA that consist of one original DNA strand and one newly synthesised DNA strand
• ATP


  The structure of ATP is: ATP → ADP (hydrolysis reaction) and ADP → ATP (condensation reaction)
• Inorganic ions


  Atoms or molecules with an electric charge, containing no carbon