Enzymes Flashcards
what are reactions catalysed by
enzymes
what are enzymees
biological catalysts
what type of protein are enzyme
globular
what do enzymes do
interact with a substrate molecules causing them to react at much faster rates without the need for harsh environment conditions
what are chemical reactions required growth called
anabolicw
where is energy released from
large organic molecules (glucose)o
how is energy released from large organic molecules
in metabolic pathways consisting of catabolic reactions (breaking down reactions)
how are these large organic molecules obtained
from the digestion of food
what is the specificity of the enzyme
each enzyme catalyses one biochemical reaction
what is activation energy
energy needs to be supplied for most reactions to start
what can enzymes help with
for molecules collide successfully and reduce the activation energy required
describe the lock and key hypothesis
only a specific substrate can fit into an enzyme’s active site
when the substrate is bound to the active site, an enzyme-substrate complex is formed
- the substrate then react and the product is formed in an enzyme-product complex
- the product is then release, leaving the enzyme unchanged and able to take part in subsequent reactions
what puts strain on the bond in the substrate
the substrate is held in such a way by the enzyme that the right atom-groups are close enough to react, the R-groups within the acitve site of the enzyme will also interact with the substrate forming temporary bonds
what is an induced-fit hypothesis
the active site of the enzyme actually changes shape slightly as the substrate enters
describe the initial intereaction between the enzyme and substrate in induced-fit hypothesis
it is relatively weak but these weak interactions rapidly induce changes in the enzymes tertiary sturcture that strengthen binding, putting strain on the substrate molecule
what are intracellular enzymes
enzymes that act within cells
give an example of intracellular enzymes
the synthesis of polymers from monomers, making polysaccharides from glucose, requires enzymes
catalase helps break down hydorgen peroxide
what supplies raw materials (substrates)
nutrients
what form are nutrients in
polymers such as proteins and polysaccharides
why do nutrients need to be broken down intosmaller components
they are too large to enter through the cell-surface membrane
how are these nutrients broken down
by enzymes through the process of digestion (extracellular enzymes)
what are extracellular enzymes
they work outside the cell that made them
how do single-celled organisms use extracellular enzymes
eg. bacteria and yeast, release enzymes into their immediate environment, extracellular enzymes break down the larger molecules (proteins) produce smaller molecules (amino acids and glucose) are absorbed by the cell
how do multicellular organisms use extracellular enzymes
the large molecules still have to be digested so smaller molecules can be absorbed into the bloodstream, from there, they are transported around the body to be used as substrates in cellular reactions