Chapter 5 Proteins Flashcards
What are the functions of proteins?
Speed up chemical reactions Defense Storage Transport Cellular communication, movement or structural support
Catalysts
Chemical agents that selectively speed up chemical reactions without being consumed in the reaction
How are all proteins structured?
By the same 20 amino acids linked in unbranded polymer
What is the bond between amino acids called?
Peptide bond
Polypeptide
Polymer of amino acids
Proteins
Biologically functional molecule made up of one or more polypeptides
What is the monomer of proteins?
Amino acid
What is an amino acid structure?
4 groups
Molecule with both amino group and carboxyl group.
At the center is a carbon atom called alpha carbon and then a variable group written as R
R group is also called?
Side chain
The R group on an amino acids determines?
The unique characteristics of a particular amino acid affecting it’s functional role
How are amino acids usually grouped?
By the properties of their side chains
What are the 3 classifications of side chains?
Non polar; hydrophobic
Polar; hydrophilic
Electrically charged; hydrophilic
What is a peptide bond?
When the carboxyl group of one amino acid is next to the amino group of another amino acid a dehydration reaction can form them together
Repeated over and over forms a polypeptide
Peptide backbone
Repeating sequence of atoms. The main chain
A functional protein is not just a polypeptide chain but
One or more polypeptides precisely twisted, folded and chilled into a molecule of unique shape
In almost every case the function of a protein depends on its ability to
Recognize and bind to some other molecule
What are the 4 levels of structure for a protein?
Primary
Secondary
Tertiary
Quaternary - arises when protein consists of 2 or more polypeptide chains
The primary structure of a protein is
It’s sequence of amino acids
The secondary structure of a protein
Has parts of their polypeptide chain coiled or folded as a result of hydrogen bonds
Tertiary structure
3D shape stabilized by interactions between side chains
Quaternary structure
Association of 2 or more polypeptides
Denaturation
Protein looses its shape and unravels
Becomes biologically inactive
