Chapter 3: Proteins Flashcards
Function #1 of proteins
Transporting Molecules
Function #2 of proteins
Enzyme
Function #3 of proteins
‘Gates’ thru membrane
Function #4 of proteins
Support/Protection
Function #5 of proteins
Movement
Function #6 of proteins
Signalling (e.g. hormones)
Function #7 of proteins
Receptors (e.g. for hormones)
Function #8 of proteins
Storage (of monomers)
Function #9 of proteins
Defense
Proteins are?
Polymers of aa’s
How many different types of aa’s exist in organisms
20
How can they act in water?
As either an acid or base
It has the capacity to?
Buffer
Which group affects an aa’s properties?
R-Group
What do you call the bond between aa’s?
Peptide bond
A chain of many aa’s is called?
A polypeptide chain
What do you call the particular 3-D shape of a protein structure?
Its ‘conformation’
How is conformation determined?
By 4 levels of structure
What is the 1st level called?
Primary level
What’s the property of the primary level?
A sequence of aa’s (covalent bonds/peptides)
What is the 2nd level called?
Secondary level
What’s the property of the secondary level?
Areas of coiling or pleaded sheets
Why does coiling and pleading occur within the secondary level?
Due to the H-bonds between atoms of the ‘backbone’ (i.e. not R-groups)
What is the 3rd level called?
Tertiary level
What’s the property of the tertiary level?
Various twists and folds
Why do various twists and folds occur within the tertiary level?
Due to various bonds with R-groups (e.g. covalent, ionic, H-bonds, hydrophobic…)
What is the 4th level called?
Quaternary level
What property gives the quaternary level its conformation?
When a protein is made up of >1 polypeptide chain (subunits) *doesn’t occur all the time
What do you call the loss of a protein’s conformation?
Denaturation
What 3 factors cause denaturation to occur?
High temperature, unfavourable pH, high [salt]
