Exam (elaborations)
AQA A LEVEL BIOLOGY Paper 1 MS 2021
- Course
- Institution
AQA A LEVEL BIOLOGY Paper 1 MS 2021
[Show more]
Seller
Follow
Labsolution
Reviews received
Content preview
AQA A-Level Biology: Paper 1 20211. 1.1 Describe the induced fit model of enzyme action and how an
enzyme acts as a catalyst.: - The substrate binds to the active site and
forms an ES complex.
- The active site changes shape slightly so it's complimentary to the
substrate.
- This reduces the activation energy.
2. 1.2 Tick one box to show which are the substrate the scientists must
add to the reaction mixture is to produce ATP.: - Adenosine diphosphate.
3. 1.3 Suggest and explain a procedure the scientist could have used to
stop each reaction.: - The nature of the enzyme by putting it in ice.
4. 1.4 Explain the change in ATP concentration with increasing inorganic
phosphate concentration: - With increasing phosphate concentration
more ES complex is form.
- And at 40 mol dm3, all active sites are occupied.
5. 2.1 Explain the advantage for large animals of having a specialised
system that facilitates oxygen uptake.: - Large organisms have a smaller
surface area to volume ratio.
- This means they overcome a long diffusion pathway.
6. 2.2 Suggest how the environmental conditions have resulted in adapta-
tions of systems using model A rather than model B.: - Water is more
dense than air.
- So it supports the gills.
1/
, 7. 2.3 A student studies figure 3 and concluded that the fish gas exchange
system is more efficient than the human gas exchange system. Use figure
3 to justify this conclusion.: - The difference of oxygen concentration
between the artery and vein is larger in the fish than the human.
- So the fish remove a greater amount of oxygen that they intake.
8. 2.4 Explain how the countercurrents principle allows sufficient oxygen
uptake in the fish gas exchange system.: - Blood and water continuously
flow in opposite directions.
- So the concentration gradient is maintained along the length of the
lamellae.
9. 3.1 Describe how one amino acid is added to a polypeptide that is being
formed at a ribosome during translation.: - TRNA brings the specific
amino acid to the ribosome.
- The anticodon on the tRNA binds to the codon on the mRNA.
- The amino acids join to form a peptide bond using ATP.
2/
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 Labsolution. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
77764 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now