1.1 monomers and polymers

what is a monomer?

smaller, repeating units that join together to form large molecules

what is a polymer?

a larger complex molecule made from many monomers joined together

give 3 examples of monomers.

• monosaccharides.

• amino acids.

• nucleotides.

give 3 examples of polymers.

• polysaccharides.

• proteins.

• nucleic acids, DNA/RNA.

give 2 polymers that are not considered to be ‘true’ polymers and a reason why.

proteins and DNA,

because monomers may change/may not all be the same in a protein or DNA molecule, so they wouldn’t be formed from repeating units

what happens in a condensation reaction?

• a chemical bond is formed between 2 molecules.

• a water molecule is released.

• a larger molecule is formed.

what happens in a hydrolysis reaction?

• a water molecule is used

• to break a chemical bond between 2 molecules.

• so a larger molecule is broken down.

why is hydrolysis important?

• larger biological molecules may be too large to be transported into cells.

• they must be hydrolysed, because monomers are easier to transport than polymers.

• smaller molecules can then be taken up by the cells and used for a number of functions and important reactions, e.g. respiration.

true or false:

polymers are simple molecules with ionic bonds.

false - polymers are giant molecules with covalent bonds