Biomolecules Flashcards
What are the essential molecules for life
Carbs
Nucleotides and nucleic acids
Lipids
Proteins
Define an organic molecule
Contains carbon
Definition of a biomolecule
Organic molecule that is commonly associated with life
Carbs
Lipids
nucleic acids
Proteins
What is the formula for carbs
CnH2nOn
What’s the glucose formula
C6H12O6
Describe carbs
Hydrophilic
Abundant
Used for structure and energy
Almost all eukaryotic cells use glucose for energy
Plants use carbs as structural
Proteins and lipids are modified by the addition of carbs
What are some monosaccharides
Simple sugars Ribose Fructose Galactose Glucose
What are disaccharides
Consists of glucose and another monosaccharides
Sucrose
Maltose
Lactose
What are polysaccharide
Glucose polymers
Store glucose in the form of polysaccharide
Glycogen
Chitin
Cellulose
Starch
What are nucleotides
Consist of one or more phosphate group a 5 carbon sugar and a 3 carbon nitrogen ring called a nitrogenous base
Nitrogenous bases
The structure of the nitrogenous base determines whether the nucleotide is
Adenosine
Cytosine
Guanosine
Thymidine
What is adenosine triphosphate
Basic molecule of energy storage in most organisms including mammals
What important signalling molecule is within cells
Cyclic AMP (cAMP) Adenosine monophosphate
Cyclic GMP (cGMP)
What is adenosine
A neurotransmitter
An energy source in many physiological chemical reactions
Guanosine triphosphate
What do lipids contain
Are they hydrophobic or Phillic
Generally hydrophobic molecules
Contain mostly carbon and hydrogen few oxygen atoms nitrogen phosphorus
What are different types of lipids
Fatty acids Glycerides Phospholipids and sphingoloipds Steroids Eicosanoids
What are the roles of lipids
Structure of cells
- waterproof so keeps insides in outsides out
- pliable
Energy source
Communication (within cells and between cells)
Saturated fatty acids
No double bonds
Solid
Unsaturated fatty acids
Double bonds
Liquid
Glycerides
Mono glycerides
One glycerol and one fatty acid
Diglyceride
One glycerol and two fatty acids
Triglyceride
One glycerol and three fatty acids
Phospholipids
One glycerol and two fatty acids
Plus a phosphate and variable R group
Phospholipids are _____ molecules which means
Amphipathic
Molecules have polar heads (hydrophilic) and nonpolar tails (hydrophobic)
R group is polar group
Phospholipid bilateral forms a __
Sheet
Droplets of phospholipids
Micelles
Liposomes have a ____ centre
Aqueous
What are sphingolipids
A sphingosine
Fatty acid
Phosphate
Variable
What are glycophospholipid
A phospholipid plus a carbohydrate
What are steroids
Consists of three six carbon rings plus one five carbon ring (17 carbons)
What roles do steroids play
Communication and cell structure
Different functional groups (R groups) confer different function
What are eicosanoids
Main chain consists of 20 carbon atoms
Derived from the fatty acid arachadonic acid
Main function of eicosanoids
Communication within cells and between cells
What are proteins
Macromolecules
Chains of amino acids
20 amino acids encoded by the universal genetic code
Amino acids
22 amino acids
2 are additional and may be incorporated
9 are essential and need to consume
11 are non essential and we can synthesize them
Acidic basic polar non polar
A short chain of amino acids are called
A peptide
Longer chains of amino acids are called
Proteins
What are the 4 structures of proteins
Primary structure(line) Secondary structure(helix sheets) Tertiary structure(ribbon) Quaternary structure (fibrous globular)
Genome
The sequence of amino acids that is encoded
Proteins are ___ of cells
Molecular tools
Insoluble protein
Soluble protein
Fibrous
Globular
How many categories of soluble proteins are there
7
What are the 7 soluble proteins
Enzymes Membrane transporters Signal molecules Receptors Binding proteins Regulatory proteins Immunoglobulins
In order for a protein to do something it must do what
Interact with or bind to other proteins molecules or ions
A molecule that binds to a protein binding site is called a __
Ligand
What are endogenous Ligands
Something natural in your body
Ie) a hormone or neurotransmitter
Example of non endogenous
A drug or toxin
Define affinity
High affinity means it binds strongly
Weak affinity means weak binding
A protein binds a ligand with ___
Affinity
Define an agonist
A ligand that binds to a protein binding site and alters the state of the protein resulting in a biological response
A hormone or neurotransmitter or a drug for example
Define an antagonist
A ligand that reduces the action of an agonist
Binds but causes no biological response
What is an allosteric antagonist
Act to block the agonist by binding to the protein away from the binding site and inactivate the binding site
Also called inhibitor or blocker
What is the rate of protein activity
Has a measurable rate
Often depends on amount of protein and concentration of ligand
Has a maximum rate (saturation)
How does amount of Protein (concentration) change the rate of activity
Reaction rate depends on the amount of protein
The more protein the fast the reaction rate is
The more workers the more work done
How does amount of ligand change the reaction rate
The amount of binding protein is held constant
the reaction rate depends on the amount of ligand up to the saturation point
Like an elevator only room for so many people
Rate of protein binding and activity can be modulated by
Isoforms (closely related proteins)
Activation
Physical factors (ph temp)
Modulation
What is modulation that alter protein binding
Covalent modification
- phosphorylation and dephosphorylation
- addition of lipid or carbohydrate
Agonists and antagonists
Phosphorylation and dephosphorylation can modulate rates of protein activity by
Enzymes called kinases covalently add phosphates
Phosphatases remove them
Phosphorylation may cause activation or inhibition
