Types of enzymes

Why are enzymes specific ?

They are specific to a particular substrate due to the shape of the active site

What are catabolic reactions and what is an example ?

They break things down , and metabolic pathway energy is required .

E.g: respiration (breaking down glucose for energy

E.g : Digestion

What are anabolic reactions?

They build things up , and are chemical reactions that are required for growth.

E.g: Photosynthesis

What is activation energy ?

Minimum amount of energy required to start a chemical reaction

What are extra cellular enzymes?

Enzymes that catalyse reactions outside of a cell

What are intracellar enzymes ?

Enzymes in the cytoplasm , so catalyse reactions inside the cell

What are hereotrophs and what is an example ?

They consume other organisms and break down nutrients. E.g: Proteins into amino acids

What is an external digestive system ?

They secrete enzymes onto the food source outside of their bodies . E.g: flies

How do extra cellular enzymes work and what are two examples of them ?

Molecules need to be broken down into smaller molecules before they pass inside the a cell so enzymes released from the cell that are extracellular can do this (as they work outside the cell )

E.g: Fungi work outside of organisms

Single-celled organisms release into their surrounding environment

What happens in the lock and key theory ?

• The substrate is held by the enzyme so that the right atom groups are close enough go to react

• R-groups in the active site of the enzyme will interact with the substrate . Temporary , weak bonds are formed

• These temporary bonds will put strain on the bonds within the substrate , this will support the reaction in taking place

What is induced fit theory ?

• Enzyme not initially a perfect fit so the active site changes shape slightly to fit the enzyme perfectly

• The interactions between the substrate and enzyme are weak as they have weak bonds between each other because they enzyme wont stay for long

• Changes occur in the tertiary structure which strengthens the the bonding and puts strain on the substrate molecule

• This leads to a weakening of the bonds in the substrate and lowers the activation energy