Exam (elaborations)
Biology AQA AS level 7401_1 Paper 1 solutions
- Module
- ATI comprehensive predictor
- Institution
- ATI Comprehensive Predictor
Biology AQA AS level 7401_1 Paper 1 solutions
[Show more]
Seller
Follow
Content preview
Biology AQA AS level 7401/1 Paper 1solutions
• The human cell then makes a complementary strand to the HIV DNA. The
complementary strand is made in the same way as a new complementary strand is
made during semi-conservative replication of human DNA. Describe how the
complementary strand of HIV DNA is made. - ANS-- there are complementary
nucleotides/bases pair
- DNA polymerase used
- Nucleotides join together (to form new strand)/phosphodiester bonds form;
Contrast the structures of DNA and mRNA molecules to give three differences. - ANS--
DNA is double stranded/double helix and mRNA single-stranded;
- DNA (very) long and RNA short;
-Thymine/T in DNA and uracil/U in RNA;
- Deoxyribose in DNA and ribose in RNA;
Describe the difference between the structure of a triglyceride molecule and the -
ANS-In phospholipid, one fatty acid replaced by a phosphate
Describe how you would test for the presence of a lipid in a sample of food - ANS-- Add
ethanol, then add water;
-White (emulsion shows lipid)
Describe how a saturated fatty acid is different from an unsaturated fatty acid -
ANS-Unsaturated has (at least one) double bond (between carbons)
This fat substitute cannot be digested in the gut by lipase. Suggest why. - ANS-- (Fat
substitute) is a different/wrong shape/not complementary
- Unable to fit/bind to (active site of) lipase/no ES complex formed;
Despite being a lipid, the substitute cannot cross the cell-surface membranes of cells
lining the gut.
Suggest why it cannot cross cell-surface membranes. - ANS-It is hydrophilic/is polar/is
too large/is too big;
Cells constantly hydrolyse ATP to provide energy. Describe how ATP is resynthesised in
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 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 denicetho. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £7.16. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79064 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now