Biological Molecules

• Monomers


  .One of many small molecules that combine to form a polymer.

  .Created through hydrolysis.
• Condensation Reaction


  .When two molecules join together with the removal of water.
• Polymers


  .A large molecule made up of small repeating units (monomers).
• Hydrolysis Reaction


  .Seperate molecules by an addition of water.
• Elements that Make Up Biological Molecules

  C, H, O N, P, S
• 3 Chemical Bonds:

  .Ionic- gain and lose electrons.

  .Covalent- share electrons.

  .Hydrogen- polar molecules.
• Monomers and their Associated Polymers

  .

  
• How is glucose stored by plants.

  As starch.
• What is the Word Equation for Aerobic Respiration? 


  .Glucose + Oxygen -> Carbon Dioxide + Water + Energy
• What are Protein Molecules Made up of?

  Amino acids.
• What are Proteins Needed for?

  To build muscle.
• What are the 3 Main Digestive enzymes?

  .Lipase

  .Proteases

  .Sucrase
• What Affects the Rate of Metabolic Reactions? 


  .High temperature causes the enzymes to denature.
• What Does Anabolic Mean? 


  .To build large molecules from smaller ones.
• What Does Catabolic Mean?

  .To break larger molecules down into smaller ones.
• What are Isotopes?

  .An element with a different number of neutrons.
• What is an Ion? 


  .An atom or molecule with a net electrical charge.
• Covalent Bond


  .Atoms share electrons with each other to fill the outer shell.

  .They become strongly bonded to each other.
• Hydrogen Bond

  .A weak interaction that occurs whenever molecules contain a slightly, negatively charged atom bonded to a slightly, positively charged hydrogen atom.
• Ionic Bond


  .When a metal atom and a non-metal atom transfer electrons.

  .(Gain or lose).

  .(+ or -).
• What are Amino Acids? 


  .Organic compounds that contain both: amino and carboxylic acid functional groups.
• Polar Molecule


  When the oxygen atom has a greater number of positive protons in it's nucleas than hydrogen.
• Prefixes

  Mono-1

  Di -2

  Tri -3

  Tetra -4

  Penta -5

  Hexa -6

  Poly -Many
• Nucleotides and Nucleic Acids Molecules and their Roles in the Cell

  Nucleotides:

  .Form the monomers of nucleic acids.

  .Help regulate many metabolic pathways.

  Nucleic Acids:

  .Carry coded instructions used in development and functioning of all living organsims.
• Lipids Molecules and their Role in the Cell. 


  .Combine with protein to make lipoproteins that can move throughout the body.

  .Can ionise hyrogen.

  .Produce steroid hormones.

  .Used to build up the cell membrane.

  .Are an energy store.
• Carbohydrates Molecules and their Role in the Cell


  .A scource of energy.

  .Form structural units.
• Water Molecules and their Role in the Cell:

  .Provide habitats for living things.

  .Form major component of the tissue.

  .Needed for chemical reactions.

  .Form up to 80% of cells.

  .Effective transport medium.
• Protein, Hormones, Antibodies and their Role in the Cell:

  .Form structural component of animals ( muscle) .

  .Act as carriers and pores for active transport and diffusion.
• Inorganic Molecules and their Role in the Cell:

  .Contributes to nervous transmission and muscle contraction. ( Sodium)

  .Cell function.

  .Metabolism
• Properties of Water: 


  .Moving constantly- inter molecular bonds are being broken.

  .H-bonds make it more difficult for molecules to evaporate.

  .The cooler the water, the less dense it will become. (Arrangement of molecules) .

  .Maximum density at 4 degrees.

  .Density goes down drastically as it approaches 0 degrees.
• What are the Four Properties of Water:

  .Ionic solutes can dissolve in water. ( Sodium Chloride) .

  .Covalent solutes dissolve due to polarity of water. (Glucose)

  .Cytoplasm of cells- 70% water- molecules and ions move around and react.

  .Molecules and ions dissolve in water- transported around living organisms.
• Cohesion and Surface Tension:

  .Water molecules closest to the surface are H-bonded to molecules below them.

  .More attracted to water molecules than to air above.

  .Gives the surface of the water ability to resist force applied to it- surface tension.

  .E.g.:

  .Columns of water in plant tissue are pulled up in xylem tissue.

  .Insects like pond-skaters can walk on water.
• Adhesion: 


  .Water molecules are attracted to other materials.

  .Exhibit capillary action.

  .Thinner diameter, more adhesion.
• High Specific Heat Capacity:

  .The amount of energy required to raise the temperature of a 1kg substance by 1 degrees celsius.

  .Water molecules require heat energy to break H-bonds before increase in temperature.

  .It takes 4.2kJ of water by 1 degree Celsius.

  .Temperature of water remains relatively stable.

  .(Organisims need a stable temp for enzyme controlled reactions), (aquatic organisms need a stable environment).
• High Latent Heat of Vaporisation:

  .Quantity of heat required to change 1kg of liquid at its boiling point completely to vapour at a constant temperature. A large amount of energy is needed to break H-bonds in water to allow it to turn into vapour.

  .Water can help cool living organisms down.

  .High temperature can damage living tissue.

  .The body can donate a lot of heat to water before it evaporates- this takes heat away from the body.
• What are monosaccharides?

  .Simplest sugar.

  .Source of energy.

  .Large number of carbon-hydrogen bonds.

  .Sweet taste.

  .Soluble in water.

  .Insoluble in polar solvents. (Benzene)

  .Can exist as a straight chain or as a cyclic molecule.

  .Single bonded carbon and one double bonded to an oxygen (carbonyl group).
• Examples of Ring structures: 


  .Hexose

  .Pentose
• Examples of Straight Chains:

  .Triose

  .Tetrose
• What is an Isomer? 


  .A molecule with the same formula, but the atoms are arranged differently.
• What are Disaccharides? 


  .Sweet

  .Soluble

  .Maltose and lactose->reducing sugar.

  .Sucrose-> non-reducing sugar.