2.2. 1-2 Basics Biochemistry Flashcards
What is a condensation reaction?
(bond making)
reaction that occurs when two molecules are joined together with the removal of H2O
What is a hydrogen bond?
a weak interaction that can occur wherever molecules contain a slightly negatively charged atom bonded to a slightly positively charged Hydrogen atom
What is a hydrolysis reaction?
(bond breaking)
reaction that occurs when a molecule is split into two smaller molecules with the addition of water
What is a monomer?
a small molecule which binds to many other identical molecules to form a polymer
What is a polymer?
a large molecule made from many smaller molecules called monomers
What is Covalent Bonding?
sharing of a pair of electrons
What do 2 monomers make?
dimer
Name the atoms of the molecule Carbohydrates and the monomer it makes as well as the polymer
Atoms: C, H, O
Monomer: Monosaccharadies e.g Glucose
Polymer: Polysacchardies e.g Starch
Name the atoms of the molecule Protiens and the monomer it makes as well as the polymer
Atoms: C, H, O, N, S
Monomer: Amino acids
Polymer: Polypeptides and protiens
Name the atoms of the molecule Nucleic Acids and the monomer it makes as well as the polymer
Atoms: C, H, O, N, P
Monomer: Nucleotides
Polymer: DNA and RNA
What does polar mean?
A polar molecule will have dipoles
Why is it important for Water to be a liquid at room temperature?
Water has low viscosity which means it can flow easily:
- Provides Habitats for living things in rivers, lakes, seas
- Form a major component of the tissues in living organisms
- Provides a reaction medium for chemical reactions
- Provides an effective transport medium e.g in blood and vascular tissues.
The density of water provides an ideal habitat for living things. Because ice is less dense than water, how does this benefit living organisms?
4°C is the freezing point of water
- Aquatic organisms have a stable environment in which to live through winter as the water molecules align themselves in a structure which is less dense than liquid water —> It doesn’t sink
- Ponds and other bodies of water are insulated against extreme cold. The layer of ice reduces the rate of heat loss from the rest of the pond
What does solvent mean?
able to dissolve other substances.
What does solute mean?
the minor component in a solution, dissolved in the solvent.
How does water’s polarity affect its solvent properties?
- Water is polar —> +ve and -ve parts of the water molecules are attracted to the +ve and -ve part of the solutes.
- Water molecules cluster around these charged parts of solute molecules or ions and will help separate them and keep them apart.
What advantages are there of Water being a good solvent?
- Molecules and ions can move around and react together in water.
- and can be transported around living things whilst dissolved in water.
- Many such reactions happen in the cytoplasm of cells which is over 70% water
What is cohesion?
Cohesionholds hydrogen bonds together to create surface tension onwater. Sincewateris attracted to other molecules, adhesive forces pull thewatertoward other molecules
What is surface tension?
- Water molecules at the surface are all hydrogen bonded to the molecules beneath them —> more attracted to the water molecules beneath than to the air molecules above
- This means the surface of the water contracts —> Gives water an ability to resist force applied to it
What are the advantages of Surface tension and cohesion?
- Columns of water in plant vascular tissue are pulled up the xylem tissue together from the roots
- Insects like pond-skaters can walk on water
Why is having a high specific heat capacity of water important?
- Living things, including prokaryotes and eukaryotes, need a stable temperature for enzyme- controlled reactions to happen properly
- Aquatic organisms need a stable environment in which to live
What is the specific heat capacity of water
4.2kJ of energy to raise the temperature of 1kg of water by 1°C
What is high latent heat of vaporisation and why is it important?
- When water evaporates, heat energy, known as latent heat of vaporisation, helps the molecules break away from each other to become a gas.
- This means water can help cool living things and keep their temperature stable.
Water is involved in reactions such as photosynthesis and in hydrolysis reactions such as digestions of starch proteins. Is it’s properties as a reactant effected?
It’s properties as a reactant does not directly draw on its polarity, but its role as a reactant is important for digestion and synthesis of large biological molecules
