Ch 4 - Enzymes Flashcards
What is a catalyst?
A catalyst is a substance that can speed up a chemical reaction, without itself being chemically changed at the end of the reaction
can a catalyst be reused?
yes
what are enzymes?
Enzymes are proteins that function as biological catalysts. They speed up the rate of chemical reactions. They remain chemically unchanged at the end of the reaction.
Why can’t proteins break down themselves, iif enzymes are proteins anyway?
not all enzymes are proteins, hence proteins cannot breakdown themselves
what is activation energy?
the energy needed to start a chemical reaction is called activation energy
How are large molecules breaking down into smaller molecules beneficial?
allows substances to be soluble in water and small enough to diffuse through the cell membrane
What are the enzymes that are involved in digestion called?
digestive enzymes
what are the 4 digestive enzymes to remember?
amylase - starch to maltose
maltase - maltose to glucose
protease - proteins to polypeptides, then to amino acids
lipase - fats to fatty acids & glycerol
2 ways enzyme-catalysed reactions can be classifies into
- reactions that build up complex substances - anablic reactions
- reactions that breakdown complex substances - catabolic reactions
How do anabolic reactions occur?
cells build up or synthesise complex substances from simpler ones.
When are digestive enzymes produces?
only when there is food in the digestive tract
what are the substances which the enzymes act on?
substrates
What are active sites?
they are grooveson the surface of an enzyme molecule
How is the substrate a key?
a substrate molecule has the matching fit with its enzyme
When is an enzyme-substrate complex formed?
it is when the substrate binds to the enzymes
What happens when the reaction takes place at the active site?
the substrate molecules are converted into product molecules. the product molecule then separates from the enzymes
