biomolecules Flashcards
what are monosaccharides?
the basic unit of carbohydrates, made of carbon,hydrogen and oxygen atoms
what is the general formula of carbohydrates?
(CH2O)n
n can be 3,5 or 6,they can be classified according to the number of carbon atoms in the molecule
n=3-trioses n=5-pentoses n=6-hexoses e.g fructose, glucose,galactose
what are disaccharides?
-disaccharides is what is formed when two monosaccharides are joined together e.g glucose+ fructose=sucrose
what is a dehydration/condensation reaction?
a reaction where water is release, energy is required
what is a glycosidic bond?
a bond that holds two monosaccharides together
what is condensation polymerisation?
a serious of condensation reactions that add units together until very large polysaccharides are formed
what do the properties of a polysaccharide depend on?
solubility
-the length
-the extent of branchinng(weather the units are being added to the side of the chain or its ends)
-whether the chain is straight or coiled
compare normal haemoglobin to glycated haemoglobin…
-normal haemoglobin transports 4 oxygen molecules by binding to 4 iron atoms inside each haem group while glycated haemoglobin permanently binds to proteins like haemoglobin after prolonged exposure to elevated blood sugar
what are the different types of lipids?
-saturated fats
-unsaturated fats-carbon-carbon double bond
-cis saturated fats
-trans-unsaturated fats
what are the two types of unsaturated fats?
-monounsaturated-single double bond
-polyunsaturated-multiple double bonds
what are cis unsaturated fats?
-usually naturally occurring fats where the hydrogens are on the same side of the double bonds and this creates a kink these fats are likely to be a liquid at room temp
what are trans-unsaturated fats?
-manufactured fats where the hydrogens are on opposite sides of the double bond, there are no kinks and these fats are likely to be solid at room temp
-they are associated with cardiovascular diseases
why are saturated and trans fats bad?
they increase the LDL levels in the blood and this is associated with heart disease
why are unsaturated fats good?
-they help reduce LDL levels in the blood and so this decreases the cholesterol to HDL ratio helping take cholesterol to the liver where it can be disposed
what is cholesterol?
-a lipid which is amphipathic, it is an essential component of cell membranes and it came before steroids, vitamin D and bile acids
define amphipathic…
-having both hydrophobic and hydrophilic regions
how is cholesterol transported?
-by lipoproteins
what is HDL and LDL?
-HDL-good cholesterol trasported to the liver for recycling
LDL-bad cholesterol-accumulates in the inner wall of the arteries
what are phospholipids?
-lipids that are amphipathic with a hydrophilic head and hydrophobic tail and are joined by glycerol
-they form bilayers e.g the cell membrane
what are proteins?
-they are built on monomer units called amino acids and interact with each other and other biological macromolecules to form assemblies
-there are 20 amino acids, they are zwitterions at a neutral pH and are amphoteric
define amphoteric…
can react both as a base and an acid
what is the structure of a protein?
-an amine NH2
-a carboxyl (COOH) functional group
-a side chain (R group) specific to each amino acid
how can we classify amino acids by their R groups?
-Non-polar have hydrophobic R-groups
-Polar have hydrophilic r-groups
-Acidic have negatively-charged R groups
-basic have positively-charged R groups
define hydrophobic and hydrophilic…
-hyrophobic-does not dissolve in water
-hydrophillic-tendency to interact with water at a biological pH
