bio molecules

• Name 5 roles of water

  It is a reactant in lots of chemical reactions

  It is a solvent

  It transports substances

  It helps with temperature control

  It is a habitat
• Describe the structure of a water molecule

  One atom of oxygen

  Two atoms of hydrogen
• What makes water polar?

  It has a partially negative charge on one side due to the negative oxygen

  It has a partially positive side due to the positive hydrogen
• What is hydrogen bonding?

  The partially negative oxygen atoms attract the partially positive hydrogen atoms of other molecules
• What is specific heat capacity?

  The amount of energy needed to raise the temperature of 1 gram of a substance by 1 degree celsius
• How do hydrogen bonds give water a high specific heat capacity?

  The hydrogen bonds between water molecules can absorb a lot of energy, so it takes a lot of energy to heat up the water
• How does having a high specific heat capacity make water a good habitat?

  It means that the water does not experience rapid temperature changes
• Why does water have a high latent heat of evaporation?

  It Takes a lot of energy to break the hydrogen bonds between water molecules, so a lot of energy is used up when it evaporates
• Why is it useful that water has a high latent heat of evaporation for living organisms?

  It means that water is great for cooling things, for example, some mammals sweat when they are hot to cool the surface of the skin
• What is cohesion?


  The attraction between molecules of the same type
• Why are water molecules very cohesive?

  because they are polar
• What are the advantages of water being cohesive?

  It helps water flow, making it great for transporting substances

  It helps water be transported up plant stems in the transpiration stream
• Why is water a good solvent?

  it is polar, the slightly positive end will be attracted to the negative ion, and the slightly negative end will be attracted to the positive ion

  This means that it will get totally surrounded by water molecules and dissolve
• Why is water less dense as a solid than a liquid?

  Water molecules are held further apart in ice than they are in water because each water molecule forms four hydrogen bonds to other water molecules, making a lattice shape
• Why is it useful that ice floats on water?

  In cold temperatures, ice forms an insulating layer on top of water and so the water below does not freeze.
• What are the monomers that make up carbohydrates?

  monosaccharides
• How many carbon atoms does glucose have?

  6 - hexose monosaccharide
• What is the difference between alpha and beta glucose?

  Alpha glucose hydroxyl group on c1 is down

  Beta glucose hydroxyl group on c1 is up
• What is the function of glucose?


  It is the main energy source in animals and plants
• Why can glucose easily be transported?


  It is soluble
• How many carbon atoms does ribose have?

  5 - pentose monosaccharide
• What elements are in carbohydrates?


  carbon, hydrogen, oxygen
• What is the ratio of carbon to hydrogen to oxygen in carbohydrates?

  1 carbon : 2 hydrogen : 1 oxygen
• How do monosaccharides join together?

  By glycosidic bonds
• What is a condensation reaction?

  a hydrogen atom on one monosaccharide bonds to an OH group on the other, releasing a molecule of water
• What is a hydrolysis reaction?

  When a molecule of water reacts with the glycosidic bond, breaking it apart
• What is a disaccharide?


  two monosaccharides joined together
• How is maltose formed?

  Alpha glucose + Alpha glucose
• How is sucrose formed?

  Alpha glucose + fructose
• How is lactose formed?

  Either alpha or beta glucose + galactose
• What is a polysaccharide?


  When more than two monosaccharides are joined together
• What is the function of starch?

  It is the main energy storage material in plants
• What do plants store excess glucose as?

  Starch
• What two polysaccharides make up starch?

  amylose and amylopectin
• Describe amylose


  A long unbranched chain of alpha glucose

  Coiled structure

  Compact - good for storage

  Joined by 1-4 glycosidic bonds
• Describe amylopectin


  Made by 1-4 glycosidic bonds

  Some 1-6 glycosidic bonds

  Branched structure

  Very compact

  Free ends where glucose can be added or removed

  Insoluble
• What bonds form between two glucose molecules?

  1-4 glycosidic bonds
• What molecules make up cellulose?

  Beta glucose molecules
• How do beta glucose molecules join together?

  They join by 1-4 glycosidic bonds

  Every other molecules is flipped 180 degrees
• Describe cellulose


  Long

  Unbranched