This piece of work is to help with the P5 Unit 13 Applied Science 2010 - My teacher has signed this assignment off which means that it does meet the grading criteria. Hope it helps, all the best.
Please take note that this document cannot be copied and I would appreciate if you respect my work an...
P5 - use laboratory methods to investiate aators that afeat the
enzyme rate o reaatonn
Pepsin is an enzyme present in the juices secreted by the glands in the stomach walls (gastric juice).
Gastric juice contains hydrochloric acid which has a PH 2. The functon of it is to destroy harmful
bacteria that may be present in the food, also provides the optmum PH for pepsin to work. Pepsin
type of protease called endopeptdase. The pepsin hydrolyses peptde bonds within polypeptde
molecules. Pepsin hydrolyses large polypeptdes into smaller polypeptde chains, but does not
release amino acids.
Equipment listn
- Goggles
- Test tube
- Biurette A (NaOH)
- Biurette B (Copper Sulphate)
- Syringe
- Pipette
- Beakers
- Water bath with the temperature of 37 degrees
- Stop clock
Methodn Biuret test or proteinsn
- Add 5 ml of Albumen protein into the test tube using the syringe.
- Put 1 cm3 of Biurette A (NaOH) and give the test tube some heat by holding the tube with a
hand.
- Then add drop by drop of the biurette B which is copper sulphate, the colour change from
blue to purple will appear.
- Observe the increase of the formaton of the purple precipitate indicatng the presence of
protein. Optmum conditons for experiment imitatng the conditons present in the
stomach.
Methodn Conditons and aators afeatni enzyme reaatonsn
1. Place 5 test tubes into the test tube rack. Prepare the water bath.
2. Place 10 ml of Albumen into 5 tubes.
3. Label all of the test tubes with numbers 1-5.
4. Then add 2ml of hydrochloric acid and 2 ml of Pepsin into the test tube 1.
5. Place 2 ml of dilute water and 2ml of pepsin into the test tube 2.
6. Put 2 ml of Sodium Hydrogen Carbonate and 2 ml of pepsin into the tube 3.
7. Put 4 ml of hydrochloric acid into the test tube 4 (use as a comparing sample).
8. Put a boiled pepsin and 2 ml hydrochloric acid into the tube 5.
9. As soon as the pepsin is placed into the test tube, put the rack with test tubes into the water
bath and start the stop clock.
10. Make sure you record the results and check to see the colour change every minute.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller musix. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $4.53. You're not tied to anything after your purchase.
