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• Enzymes are molecules that help in speeding up the chemical reactions that occur in cells, a function known as catalysis.
• Enzymes are essential to the body’s normal functions.
• Many enzymes end with the suffix -ase.
• Amylase is an enzyme found in saliva that helps digest starch.
• Trypsin is an enzyme found in the small intestine that helps break down proteins.
• Phase 1 results in the formation of an unstable six-carbon molecule, which spontaneously splits into two 3-PGA.
• Phase 2 is termed as reduction because the process involves the gain of electrons from the NADPH (reduced).
• Phase 3 is termed as regeneration because the process involves the re-formation of NAD+ from NADH.
• In Phase 2, ATP and electrons donated from NADPH reduce molecules of 3-PGA into G3P.
• Helicase is an enzyme that helps in unwinding DNA in the process of replication.
• Lactase is an enzyme that helps in breaking down the sugar lactose.
• The primary structure of a protein refers to the specific sequence of amino acids in a polypeptide chain.
• The secondary structure refers to the protein’s folding pattern.
• The tertiary structure refers to how the polypeptides form the shape of the molecule.
• The quaternary structure refers to the subunits of the protein.
• A binding site are amino acid residues that function to bind or accommodate the substrate molecule.
• A catalytic site are amino acid residues in the active site that serve to speed up or catalyze the reactions once binding has occurred.
• A substrate is a molecule that the reactions of which are catalyzed by the enzymes.
• A product is produced by the enzyme once the enzyme and substrate are bound to each other and the reaction has occurred.
• Lock-and-Key: The specific shape between the active site and the substrate allows only that type of binding to occur between these two molecules.
• Induced Fit: Interaction is initially weak but the bond strengthens as the active site is modified.
• Oxidative phosphorylation is the final step in cellular respiration, occurring in the mitochondria and linked to a process known as electron transport chain.
• An endergonic reaction, such as photosynthesis, is a reaction that requires energy to be driven, with the activation energy for the reaction typically larger than the overall energy of the exergonic reaction.
• The light-dependent reactions (or simply light reactions) are named so because they only occur when solar energy is available, with pigment molecules capturing kinetic energy from photons and storing it as potential energy in the chemical bonds of two molecules, ATP and NADPH.
• The light-independent reactions (Calvin cycle) are named so because energy from photons is not directly required for the chemical reactions to proceed, with phase 1 of the reactions termed as carbon fixation because the process involves incorporating carbon atoms from an inorganic source into an organic molecule, catalyzed by the enzyme RuBisCo.
• Substrate-level phosphorylation is the easiest type of phosphorylation to understand, involving the direct synthesis of ATP from ADP and a reactive intermediate, typically a high energy phosphate-containing molecule.
• An exergonic reaction, such as cellular respiration, is a reaction that releases free energy in the process of the reaction, with kinetic energy being the energy of motion and potential energy being a stored energy whose capacity to accomplish work is not being used at the moment.
• Photophosphorylation is the process of utilizing light energy from photosynthesis to convert ADP to ATP, synthesizing energy-rich ATP molecules by transferring the phosphate group into ADP molecules in the presence of light.
• The structure of ATP involves three phosphate groups attached to a molecule of adenosine.
• In cells, potential energy is in the form of chemical energy stored in the chemical bonds of biomolecules.
• Catalysis is the speeding up of reaction rates that are specific to the type of substrate and enzyme involved.
• ATP energizes other molecules in cells by transferring phosphate groups to those molecules.
• Each ATP molecule is negatively charged and repels each other, breaking the bonds releases energy.
• The process of hydrolysis releases energy to drive various biological processes, similarly, a battery is drained when it is used in flashcards and other electrical devices to perform work.
• Law of conservation of energy states that energy cannot be created nor destroyed; rather, energy can be changed from one form to another.
• Energy is defined as the ability to do work or bring about a change, allowing organisms to carry out different life processes, including growth, development, metabolism, and reproduction.
• Entropy is used to indicate the relative amount of disorganization of a system, it is the measure of randomness, the more disordered a system is, the higher is its entropy.
• Cells need to regulate enzyme activity for the benefit of the organism.
• There are two types of enzyme regulation inhibitors: chemical modifications and competitive inhibitors.
• Noncompetitive inhibitors bind to enzymes outside of the active site, potentially modifying the enzyme’s structure and reducing the active site’s capacity to bind to substrates.