|Biology||A Level||£20 /hr|
|Chemistry||A Level||£20 /hr|
A mole is a unit of measurement for the amount of a substance. One mole is 6.02 x 10^23 particles in a substance, known as Avogadro's constant. This is because this is the number of atoms in 12g of Carbon- 12(the relative atomic mass of the carbon atoms). The molar mass is always equal to the atomic mass of an atom, for example 1 mole of oxygen is equal to 16 grams.see more
A mutation is a change in the genetic composition of the DNA. It is often caused by an accidental insertion, deletion or swapping of a single base however whole genes can also move.
SNPs, or single nucleotide polymorphisms, are the most common type of mutations. They mostly occur in the non-coding region of DNA however they can occur in the coding region, within genes. This can sometimes be harmless, if that part of the DNA still codes for the same amino acid in a protein but if it codes for a different amino acid, it can change the shape and therefore the function of the protein. Sickle Cell anaemia is one of the most well known diseases caused by an SNP. SNP's are an example of a point mutation
Mutations can be caused by chemicals, radiation by natural causes.see more
An enzyme is known as a biological catalyst. This is because they can speed up reactions by providing an alternative pathway, lowering the activation energy of the reaction. They are normally composed of a protein and a non protein (co-factor). The enzyme has an active site, where the substrate/reactant binds. Enzymes are substrate specific; you can think of this like a "Lock and Key". Only a certain substrate can bind to the active site, just as only a certain key can fit into a lock. Enzymes can be denatured ( their shape changes and the active site no longer works as it it also a different shape) by changing the pH or the temperature of where you find the enzyme.see more