Flashcards by , created almost 6 years ago

Leaving Certificate Biology (Enzymes) Flashcards on Enzymes, created by eimearkelly3 on 08/12/2013.

Created by eimearkelly3 almost 6 years ago
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Question Answer
Metabolism The sum of all the chemical reactions that take place in an organism
cellular energy sources of energy that are capable of being released by reaction within a cell
A catalyst Speeds up a reaction without being used up in the reaction
Enzymes are biological catalysts (proteins)
some metabolic reactions controlled by enzymes photosynthesis respiration digestion protein synthesis cell division
Shape of enymes globular ---> complex 3D shape
substrate the substance with which an enzyme reacts
product the substance(s) the enzyme forms
denatured the specific 3D shape of the enzyme has changed and will no longer fit the substrate (generally irreversible)
factors affecting enzyme activity temperature ph
catabolic enymes break complex molecules down into simple molecules e.g. amylase breaks starch down into maltose (found in saliva, the pancreas, and germinating seeds)
anabolic enzymes convert simple molecules into more complex molecules e.g. DNA polymerase forms and repairs DNA
Active site The part of the enzyme that combines with the substrate
The induced fit model the enzyme-substrate complex
immobilised enzymes are attached to, or fixed to, each other or an inert material (not free in solution)
bioreactor a stainless steel vessel used to produce useful substances from the activities of biological agents
bioprocessing the use of enzyme-controlled reactions to produce a product / the use of biological materials (organisms, cells, organelles, enzymes) to manufacture commercial products or treatment procedures of commercial, medical, or scientific interest e.g. drugs, vaccines, antibiotics
use of immobilised enzymes in urine testing for illegal drugs and other chemicals
example of bioprocessing with enzymes production of glucose and fructose from sucrose using sucrase
Physical methods of immobilising enzymes Adsorption Enclosed by a membrane Trapped in a gel
Chemical methods of immobilising enzymes Bond to support Bond to each other
adsorption enzymes are physically attached to inactive supports such as glass beads, ceramics, cellulose particles or artificial polymers such as gels (all insoluble)
sodium alginate is commonly used as a gel for immobilisation. This gel is permeable to the entry of the substrate and the exit of the product. The gel prevents the exit of the enzyme
advantages of immobilised enzymes can be reused - cheaper can be recovered from the reaction vessel at the end of the process - rapidly purified immobilisation often stabilises the enzyme - reduces the amount needed cheaper than using free enzymes but just as efficient
uses of immobilised enzymes penicillin acylase --> alters the structure of penicillin to produce a wider spectrum antibiotic. glucose isomerase --> converts glucose to fructose which is used to sweeten soft drinks. lactose --> used to convert lactose into sweeter tasting sugars (glucose + galactose). These products are used to replace condensed milk in the manufacture of soft toffee and caramel.
Ideal temperature for human enzymes 37 degrees
Ideal temperature for plant enzymes 20-30 degrees
At what temperature do enzymes become denatured 50 degrees
Optimum PH for most enzymes 6-8
Optimum PH for pepsin in the stomach 2