Biological molecules Flashcards
(24 cards)
What is a polar molecule?
This is a molecule with an uneven charge.
What are the 2 types of bonds in water?
Covalent and hydrogen
Which molecule is negatively charged in water and which one is positively charges
Hydrogen is positive
Oxygen is negative
How much of our mass is made of water?
60%
Why are water molecules hard to separate
Because of hydrogen bonds,
Draw 3 molecules of water
See biology book
What are the properties of water?
High specific heat capacity Water is a solvent High latent of vapourisation Density and freezing properties High surface tension and cohesion
Describe water as a solvent
Water is a dipole so polar molecules are separated because one molecule is attracted to hydrogen and another is attracted to oxygen. Example: NaCl (Na is positive so it is attracted to Oxygen and the opposite is true for Cl)
Describe waters high specific capacity.
The amount of energy required to raise one gram of a substance by 1 degree Celsius.
High Specific heat capacity means more energy is required to raise the temperature of water. This makes is suitable for cells because then the body maintains an average body temperature.
Water has a high specific heat capacity because of strong hydrogen bods
It is also habitable by aquatic animals as the water bodies wont undergo drastic changes in temperature
Describe high latent heat of vapourisation of water
This is the amount of energy needed to evaporate a liquid.
Water has a high latent heat of vapourisation this means a lot of energy is required to cause evaporation.
This is god for cooling because the water from surroundings is used by water to break bonds.
When water freezes, energy is released this is why aquatic animals don’t freeze.
Density and freezing properties
When water goes below 4 degrees it becomes less dense.
Ice floats on water bodies and insulates them keeping aquatic animals alive.
Changes in density also affect currents and distribute nutrients around oceans.
Describe cohesion and high surface tension in water
Water molecules have high cohesion so they can move in long unbroken columns (transpiration)
High surface tension enables small animals to walk on water
What is a macromolecule?
This is a large molecule
What is a polymer?
A long chain of similar monomers in repeating units
What are organic compounds?
These are naturally occurring compounds that contain Hydrogen and Carbon
Why aren’t lipids macromolecules?
They don’t have repeating units.
Examples of monosaccharides
Glucose
Galactose
Examples of disaccharides
Maltose (a-glucose & a-glucose)
Sucrose (a-glucose & fructose)
Lactose (a-glucose & b-glucose
Examples of polysaccharides
Cellulose (b-glucose)
Starch (a-glucose, amylopectin and amylose)
Glycogen (a-glucose)
Draw a-glucose molecule
Check bio book
Draw b-glucose molecule
Check bio book
What is starch made of?
a-glucose
What is glycogen made of?
a-glucose
What is cellulose made of?
b-glucose
