PROTEIN STRUCTURE Flashcards
what is a protein?
Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues
what are the 7 functions of proteins?
contractile storage structural defence signalling transport enzymes
what is structural?
things such as hair, horns, feathers
what is the cytoskeleton?
a microscopic network of protein filaments and tubules in the cytoplasm of many living cells, giving them shape and coherence/rigidity
what is storage?
this is the sources of amino acids, such as egg whites and milk
what does proteins defence include?
antibodies, blood clotting and WBC
what does a signalling protein do?
produces receptors and hormones, such as insulin, that give negative feedback and trigger a response
examples of protein transport…
membrane channels, blood proteins
what is an enzyme?
a catalyst substance that helps speed up a chemical reaction
polymer
monomers (amino acids) joined together to form a chain
how many amino acids are there?
20
what 6 substances make up an amino acid?
oxygen hydrogen carbon nitrogen sulphur variable side chain
what do amino acids consist of?
an amino group (NH2)
a carboxyl group (COOH)
R group (one of the 20 side chains)
these all attach to a central carbon atom
what is the purpose of the side chain?
this is the part of the molecule that determines the function of the protein, aka its properties
what are bonds between monomers called?
peptide bonds
what reacts to form a polypeptide?
an amino group and an acid (the carboxyl group)
what is a polypeptide?
many peptides joined together
what is a peptide?
a compound consisting of two or more amino acids linked in a chain
what is the primary structure?
the unique sequence of amino acids that form the polypeptide (the order of amino’s basically)
what is the secondary structure?
the specific coiling or folding of the polypeptide chain
what are the 2 types of secondary structure?
the alpha helix
the beta pleated sheets
what is the tertiary structure?
this is the overall 3D structure of the polypeptide
how is the tertiary structure held together?
by either: ionic bonding, disulfide bonding or hydrogen bonds
What are the different hydro reactions?
hydrophilic and hydrophobic
attraction and repulsion