ENZYMES Flashcards
what are enzymes
biological catalysts that speed up chemical reactions
catalyse both anabolic ( building up) and catabolic (breaking down)
both extracellular and intracellular
what happens in the liver
catalase is an intracellular enzyme breaks down toxic substances to avoid cell damage
hydrogen peroxide + catalase = water and oxygen
what is activation energy
molecules that collide in the right orientation and with the right energy
what improves the rate of reaction
increased pressure
increased concentration
increased temperature
reduced volume of space
what’s the structure of enzymes
globular proteins
soluble in water
spherical shape
functions - regulation transport binding catalysis cell signalling immunity
include an active site
what is the active site
enzyme highly specific
complementary to substrate molecule
what is the induced fit model
The initial weak interactions between the substrate and the active site change the tertiary structure of the enzyme, putting strain on the bonds in the substrate molecule.
The weakened bonds in the substrate are more likely to break, causing the reaction to happen.
what does intracellular mean
enzymes used where they are made
e.g catalase
what is extracellular mean
outside the cell
polymers that are too large to enter the cell are broken down b y extracellular enzymes to be able to enter
e.g amylase
factors that affect enzymes in controlled reactions
temperature
pH
substrate concentrations
why do scientists measure the initial rate
to be able to compare with independent variable
how to calculate the reaction
change in y / change in x =gradient
what is temperature coefficient
Q = rate of reaction + difference in tempertaure / rate if reaction
what is denaturation
when the temperature is too high there are too many vibration bonds in the enzyme
causing them to break as the tertiary structure in the active site changes meaning the substrate no longer fits
