1 - Molecular Bio Flashcards
Hydrolysis=
Dehydration=
Hydrolysis= most macro molecules of living cells are broken apart(H20)
Dehydration= a way of forming macro molecules
Lipid=
Triglycerides (triacylglycerols)=
Phospholipids=
Steroids=
Lipid=any biological molecule with low solubility in water, and high solubility in non polar organic solvents.
Triglycerides (triacylglycerols)= are simply fats and oils, constructed from a 3 carbon backbone called glycerol attached to three fatty acids. Serve as a store of metabolic energy, thermal insulation, and provide padding.
Phospholipids= also built from a glycerol backbone as well, but a polar phosphate group replaces one of the fatty acids, amphipathic. Serve as structural component of membranes.
Steroids= four ringed structures, which include hormones; cholesterol being an important component. Serve as regulation of metabolic activities. Eicosanoids serve as LOCAL hormones for body temp, blood pressure, smooth muscle contraction.
In humans _____ of the amino acids are essential; meaning the body can not _______ them.
Amino acids in solution will ALWAYS carry___ depending on the _____ of the solution.
In humans 10 of the amino acids are essential; meaning the body can not manufacture them.
Amino acids in solution will ALWAYS carry one or more charges depending on the pH of the solution.
Primary structure=
Secondary structure=
Primary structure= the number and sequence of amino acids in a polypeptide chain.
Secondary structure= the alpha-helix and beta-pleated sheets are the 2ndary structure and contribute to the conformation of the protein.
Tertiary structure=
which is created by five forces:
1)
2)
3)
4)
5)
Quaternary structure=
Tertiary structure= refers to the three dimensional shape formed when the peptide chain curl and folds; which is created by five forces:
1) Covalent disulfide bonds between two cysteine amino acids on different parts of the chain.
2) Ionic interactions between acidic and basic side chains
3) Hydrogen bonds
4) Van der waals forces
5) Hydrophobic side chains pushed away from water
Quaternary structure= when two or more polypeptide chains bind together.
-denatured proteins are said to have lost their 2ndary, 3rd, and 4th structures, but after the denaturing agent is removed the protein will spontaneously reformed to its original conformation; this must mean that amino acid sequences play a role in the conformation of proteins.
Basic structure of an amino acid.
R
|
H2N–C–COOH
H
Nucleotides= are composed of:
1)
2)
3)
Nucleotides= are composed of:
1) Five carbon sugar
2) Nitrogenous base
3) Phosphate group
Nucleosides=
ATP=
Cyclic AMP=
NADH & FADH2=
Minerals=
Nucleosides= have all but the phosphate group (1&2)
ATP= source readily available for energy in the cell
Cyclic AMP= important component in many second messenger systems
NADH & FADH2= coenzymes involved in the Krebs cycle
Minerals= are the dissolved inorganic ions inside and outside the cell; and act as cofactors for assisting enzyme or protein function.
Enzymes=
Substrates=
Active site=
Enzymes= are typically globular proteins, but sometimes nucleic acids as act as them. Its function is to act as a catalyst for a reaction: lowering the activation energy and increasing the rate of rxn. They are not consumed or permanently altered by the rxn. They also do not alter equilibrium of the reaction.
Substrates= the reactant(s) of which an enzyme works.
Active site= the position of where the enzyme binds to the substrate; usually numerous non covalent bonds.
Enzyme-substrate complex=
Enzyme specificity=
Induced fit=
Cofactor=
Enzyme-substrate complex= the enzyme bound to the substrate.
Enzyme specificity= the idea that an enzyme is designed to work only on a specific substrate or group which is related to that substrate.
Induced fit= the model where the shape of both the enzyme and substrate will alter upon bonding.
Cofactor= non-protein components that many enzymes require to reach that optimal level. Cofactors can be coenzymes or metal ions. (ATP is a cosubstrate which is a coenzyme) Coenzymes are often vitamins.
Irreversible Inhibitors=
Competitive inhibitors=
Noncompetitive inhibitors=
Irreversible Inhibitors= agents which bind covalently to enzymes and disrupt their function.
Competitive inhibitors= compete with the substrate by binding reversibly with noncovalent bonds to the active site.
Noncompetitive inhibitors= bind noncovalently to an enzyme at the spot other than the active site and change the conformation of the enzyme.
Zymogen (proenzyme)=
Allosteric interactions=
Zymogen (proenzyme)= inactive form of the enzyme.
Allosteric interactions= modification of the enzyme configuration resulting from the binding of an activator or inhibitor at a specific binding site on the enzyme.
Negative feedback (feedback inhibition)=
Positive feedback=
Positive cooperativity=
Negative feedback (feedback inhibition)= one of the products downstream in a reaction come back and inhibit the enzymatic activity in an early reaction.
Positive feedback= where the product returns to activate the enzyme.
Positive cooperativity= the first substrate changes the shape of the enzyme which allows it bind easier to other substrates; negative cooperativity exists as well.
Metabolism:
1)
2)
3)
Metabolism:
1) Macromolecules are broken down into their constituent parts like amino acids, fatty acids, monosaccharides, releasing little or no energy.
2) Constituent parts are oxidized to acetyl CoA, pyruvate, and other metabolites then forming ATP and reduced coenzymes (NADH & FADH2) in a process that doesn’t utilize oxygen.
3) If oxygen is available the cell uses these metabolites and goes into the citric acid cycle and oxidative phosphorylation to form large amounts of energy (three compounds above) otherwise the coenzymes and other by products are expelled as waste or recycled.
Respiration:
Equation:
Respiration: the second and third stages, the energy acquiring stages. Oxygen used= aerobic; oxygen not used= anaerobic.
Glucose + O2 –> CO2 + H20; oxygen is the final electron acceptor and therefore is need for aerobic respiration.
