This is A-level biology notes on biological molecules. This includes the roles of inorganic ions in animals and plants, the properties of water that make it so vital to life
The structure and formation of monosaccharides, disaccharides, polysaccharides. as well as alfa and beta isomaration
The ...
Magnesium (Mg2+) is an important constituent of
chlorophyll and essential for photosynthesis. If a plant is
derived from magnesium it goes yellow and this is called
chlorosis. Mammals also need magnesium for bone
growth.
Iron (Fe2+) is a constituent of haemoglobin which
transports oxygen though red blood cells. When we don’t
have enough iron it is called anaemia.
Phosphate (PO3-) are used in making nucleotides
including ATP. They are also found in phospholipids
which make up biological membranes.
Calcium (Ca2+) is an important structural component of
bones and teeth in mammals. Plant cell walls also have a
calcium component.
Water
Water is a polar molecule which means it has a positive
and a negative end to it. This means that it can be used
as a universal solvent as all polar and ionic compounds
can dissolve in it.
Water can also form Hydrogen bonds due to its
electronegativity these bonds are strong and here is a
large number in water giving it properties vital for life.
Water is a metabolite which means it is used in many
mechanical reactions. For example hydrolysis and
condensation reactions.
Water has a high specific heat capacity which prevents
large fluctuations in water temperature and high latent
, heat of vaporisation which helps us with temperature
control as we use energy to vaporise sweat.
Water also has cohesion witch causes molecules to stick
together as well as sticking to surroundings therefore
allowing the water to be drawn up the xylem. This also
allows high surface tension allowing insects to walk on it
such as the pond skater
Water has a high-density supplying buoyancy to aquatic
organisms. Ice is less dense then water as the hydrogen
bonds are further apart. Ice is also a good insulator.
Water is transparent allowing plants to continue to
photosynthesis.
Carbohydrates
monosaccharides
Carbohydrates are also known as saccharides and there
are different types including monosaccharides,
disaccharides and polysaccharides.
Monosaccharides are single sugars and have the general
formula cn(H2O)n with the n representing the number of
carbon atoms. Monosaccharides are named after there
number of carbon atoms for example triose has 3 carbon
atoms.
Examples of monosaccharides are glyceraldehyde
(triose) ribose and deoxyribose (pentose) and a-glucose,
b-glucose, fructose and galactose (hexose)
disaccharides
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller jessdrew. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.50. You're not tied to anything after your purchase.
