describe how a genetic mutation of the gene coding for lactase can lead to lactose intolerance.

-A genetic mutation within the lactase gene, for example base substitution, changes a codon -This codon codes for a different amino acid to be transcribed and translated-Therefore the sequence of amino acids(primary structure) in the polypeptide is altered -This causes the polypeptide to fold differently (tertiary structure), therefore changing the shape of the enzyme active site.-The shape of the active site is specific to lactose.-The substrate (lactose) is no longer complementary to the active site, and so no enzyme-substrate complexes are formed, and the lactose cannot be broken down, causing lactose intolerance.

Answered by Jessica M. Biology tutor

2502 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

Describe the structure of DNA in the eukaryotic cell


Outline the process of the primary immune response to a pathogen.


How exactly do you explain mitosis?


What is an enzyme? Can you provide an example of an enzyme found in plants and describe its function? (4 marks)


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences