Enzymes Flashcards
To which group of molecules do enzymes belong?
Protein
What is an enzyme?
Biological catalyst
Where in the cell are enzymes produced
Ribosome
What is meant by enzymes enzymes optimum pH
Enzymes working at its best rate at certain pH level
What is denatured enzyme
Enzyme has lost its shape can no longer carry out its function
Name anabolic process carried out by plants
Photosynthesis
Name the factors that influence the activity of an enzyme
- pH
- Temperature
- Enzyme concentration
- Substarte concentration
Name a small molecules which are building blocks for these biomolecules
- Protein- amino acids
Name a difference between catabolic and anabolic
- Catabolic- respiration (Large molecules break down to form small ones)
- Anabolic- Photosynthesis (Small molecules form a larger molecule)
What is meant by specify of an enzyme?
Only one particular substrate fits the shape of an active site
Explain how enzymes work
- Subsrate combines with active site of enzyme (Active site theory- the active site is complementary shape to substrate)
- Active site changes shape slightly to better fit the substrate (Induced fit model)
- Temporary enzyme-substrate complex is produced
- Substrate changes into the product
- Products leave active site
- Active site returns to original shape and can now accept a new substrate
State three advantages of using an immobilised enzyme in a bioreactor
- Easy to recover
- Easy to re-use
- Product is pure
What is a bioreactor?
vessel used to make a product
What is meant by immobilisation?
Enzymes are attached to an inert material
Name a substance used to immobilise enzymes
Sodium Alginate
Give one application of a named immobilised enzyme. In your answer refer to substrate, enzyme and product
- Convert Penicillin to different forms to produce new antibiotics
Describe how you immobilised an enzyme in the course of practical work
- Add sodium alginate to 10cm of distilled water (Traps enzyme)
- In a different beaker add 2g of yeast to water (Yeast contains an enzyme called sucrase)
- Add the yeast to alginate
- In a large beaker dissolve 1.5g of calcium chloride into 100cm water (Calcium hardens the beads)
- Draw 10ml of this yeast-sodium alginate mixture into a syringe and stand over the beaker of Calcium Chloride
- Mixture will drop in water forming beads
- Beads are calcium alginate and have yeast trapped/immobilised in them
Describe how you examined the application of the immobilised enzyme
- Add the beads to sucrose
- Sucrose solution filters down through the beads and drops of glucose are made
- The drops of glucose are tested using clinistix (Test strips for glucose)
Name the enzyme and substrate you used when investigating heat denaturation
Enzyme- Catalase
Substrate- hydrogen peroxide
Briefly explain how you carried out the experiment for heat denaturation
- Add catalase, washing up liquid and pH buffer to a graduated cylinder
- Add hydrogen peroxide to test tube
- Stand both in water bath @25C
- Add hydrogen peroxide to cylinder
- Note if foam produced
- Boil catalase for 10 minutes and repeat above steps
- Result: No activity in boiled catalase as enzyme is denatured
Name the enzyme you used when you carried out the experiment into the edict of pH on the rate of enzyme activity
Catalase
State the source of enzyme Catalase
Celery
State the substrate of this enzyme Catalase
Hydrogen peroxide
Explain why the changing pH would have an effect on enzyme activity
Active site is denatured
How did you measure the rate of enzyme activity when carrying out the effect of pH
Volume of foam produced per minute
What is the chemical nature of enzymes?
Protein
What is the molecular shape of an enzyme
Folded
Why is it necessary to keep the pH constant in the course of this investigation
to only have one variable
How did you keep the pH constant
pH buffer
How did you vary temperature in the course of the investigation
Water-bath at different temperatures
How did you know the enzyme was working
Foam was produced due to washing up liquid trapping the oxygen
What is meant by the term specificity in relation to enzymes?
Only acts on one substrate
In each of the following cases state whether the process is anabolic or catabolic
- Protein synthesis
- Conversion of ADP to ATP
- Anabolic
2. Anabolic
Apart from C, H, O there is another element always present in enzymes
Nitrogen
“Enzymes are essential for metabolism”
Enzymes control metabolic reactions
Give one example of the use of immobilised enzymes in bioreactor. In your answer name the enzyme, the substrate and the product
converts penicillin to new antibiotics
penicillin—-(penicillin acylase)—-> New antibiotics
