Functional Groups and Bio Intro Flashcards
Polar
Have a charge, dissolves in water
Polar Functional Groups
Hydroxyl, Carbonyl, Carboxyl, Amino (NH2), Sulfhydryl (SH), Phosphate (OPO32-)
What is an Acid
Proton Donor
Polar Functional groups in amino acids
Amino group and Carboxyl (acid), Sulfhydryl (SH)
Is an amino group an acid?
They can function as both acid and base. In amino acids, they function as a base.
Sulfhydryl group purpose
Involved in the folding of proteins. Has the ability to form disulfide bridges in proteins
Purpose of ATP
Energy source for muscle contraction
Guanosine Triphosphate purpose
Energy source for Protein synthesis
Non-polar functional group
CH3, hydrophobic
Macromolecules
large organic polymers formed from monomers
4 classes of macromolecules
proteins, lipids, nucleic acids, and carbohydrates
Catabolism
Breaking down macromolecules to release energy. Opposite of Anabolism
Which cells in the body use proteins?
All of them.
Polypeptides
Polymer of amino acids linked by peptide bonds.
Structure of proteins
Consists of one or more polypeptide chains
7 functions of proteins
Structural support, transport, hormonal, receptor, movement, defensive, enzymatic
Collagen
Protein for structural support. Present in animal connective tissue.
Na, K-ATPase
Transport protein that transports NaK across the membrane
Hemoglobin
Protein that transports oxygen
Insulin
Hormonal protein - first synthesized by Canadian (don’t have to know)
Receptor Protein
Detect chemical signals released by other cells
Actin and Myosin
Proteins for muscle movement
Defensive Proteins
Antibodies
Enzymes
Substance that accelerates chemical reactions (biological catalyst)
How many different amino acids are used for protein synthesis in biological systems?
20
Zwitterion
dipolar ion
3 ionic states of amino acids
in acids - acts as base, one additional charge
In base - acts as acid, one less charge
Neutral - Zwitterion - neutral ion
Differentiating amino acids
How to differentiate amino acids
look at R group (side chain)
Alpha carbon
Central carbon of amino acid
How many hydrophobic amino acids?
9 - derivatives of CH3 - nonpolar
How many charged hyrdophilic amino acids
5
Two types of hydrophilic amino acids
charged, uncharged
How do you draw amino acids and polypeptides
From n-terminus (amino end) to C-terminus (carboxyl end) -left to right
How long are polypeptides
A few amino acids in length to thousands
Isoelectric point
pH at which a molecule has no net charge
How many different polypeptides
Each polypeptide has a unique linear sequence of amino acids and isoelectric point
What determines the isoelectric point of a polypeptide
R-chain
What determines the primary protein structure
DNA sequence
Two models for protein structure
Ribbon model and space filling model
Secondary Structure
Visual, repeating structure -amino acids close together, backbone interactions
Two types of secondary structure
Alpha helix and beta pleated sheet
Amino acid residues
Individual amino acid after they link up with others to form polypeptide
Alpha helix shape reason
H bonds form between amino acid residues located 4 amino acid places apart. H bonds force helical structure, otherwise wouldn’t be able to form.
How are beta strands depicted
As flat arrows pointing towards the Carboxyl end (c-terminus)
What keeps beta pleated sheets together
Hydrogen bonds
Distance between H bonds of beta pleated sheets
No exact distance, unlike Alpha helix
What reinforces the two types of secondary structures?
H bonds between the CO and NH groups of the polypeptide backbone.
Phospholipid bilateral structure
Hydrophilic heads and hydrophobic tails.
Only amino acid with SH
Cysteine
Types of bonds which contribute to tertiary structure
Disulfide bridges, H bonds between charged Sid chains
Ionic bonds between charged side chains (salt bridge)
Hydrophobic interactions between non polar side chains.
How is a salt bridge formed?
Positive and negative r groups fold onto each other and form a salt bridge (ionic bridge)
Hydrophobic side chain interaction
Non polar side chains fold onto each other to escape aqueous environment.
How strong are disulfide bridges?
Very strong - a type of covalent linkage
How do you break salt bridges?
Add salt
How do you break disulfide bridges?
Increase temperature significantly
When is a quaternary structure visible?
When a protein is made of more than one polypeptide
Which forces hold together the quaternary structure?
Same as tertiary (covalent, weak)
Quaternary structure of collagen
3 helical polypeptides supercoiled into a triple helix
Quaternary structure of Hemoglobulin
Globular protein composed of 4 polypeptides
Number of polypeptides that make up Na, K-ATPase
2-3
