Enzymes

Example of inhibitors

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what are enzymes?

3D tertiary globular proteins that act as biological catalysts that are reusable

how does the PH of the solution affect enzyme action?

PH (measure of hydrogen ion concentration). Each enzyme has an optimum PH. A change in PH reduces its effectiveness and can eventually denature it. This is because the active site is partly determined by the hydrogen and ionic bonds, change in H+ions affects the bonding of active site and cause it to change shape

what is a metabolic pathway?

a chain of reactions, when the product from one reaction is then used as the reaction for the second reaction e.g respiration

what is the induced fit model?

a model that suggest that the enzyme changes its shape to accommodate the substrate. by doing this the enzyme puts strain on the substrate, causing the bonds to break and allowing activation energy to be lowered (glove and hand model)

What is the lock and key model?

a model that suggest that the substrate is a key that fits into the active site lock to be broken down

what is a non competitive inhibitor?

a molecule,not similar in shape to the substrate,that attaches itself to a site that is not the active site (allosteric site). it alters the shape of the active site so substrates can't occupy it, denaturing the enzyme to prevent further reactions

how does temperature affect enzyme action?

a rise in temperature increase kinetic energy, meaning more collisions, meaning more often substrates and enzymes collide for a reaction to occur, increasing rate of reaction. However too high temperature cause the enzyme to denature

Denature

active site changes shape permanently

how can you measure the rate of an enzyme reaction?

by measuring formation of product or disappearance of the substrates

what is the structure of an enzyme and how does it relate to their function?

made of amino acids with a hollow depression (active site), to allow substrate to fit into depression/active site to be broken down into a smaller molecule (substrate)

what is a competitive inhibitor?

something with the same molecular shape to the substrate, which enters active site to slow down or stop reactions competes with substrates for active site

what 3 factors affect enzyme action:

temperature, PH, substrate concentration

how does substrate concentration affect enzyme action?

the rate of the reaction increase proportional to the amount of substrates that are added, until all active sites are occupied

what is the function of enzymes?

to act as catalysts to speed up chemical reactions by lowering the activation energy, meaning reactions can happen at lower temperatures than normal.

what are inhibitors used for?

to control metabolic pathways, by slowing down/stopping reactions at different stages, acting as negative feed back

Optimum

where reaction works at its best