The following document contains my structured and easy to read condensed notes filled with great diagrams for all of Biology AQA A level. The boxes for every chapter contain all the concepts you need to know for each chapter with the notes are followed below. Notes are bite sized and will help with...
The Control of Gene Expression
● Gene expression
○ Stem cells and totipotency
○ Regulation of protein synthesis
○ Gene expression and cancer
○ DNA-histone complex
○ Epigenetic control
○ Genome mutations
○ Genome project
■ DNA sequencing
■ Proteome
● Recombinant DNA technology
● Mutations are changes to the base sequence of DNA
○ Substitution
○ Deletion
○ Addition
○ Duplication
○ Inversion
○ Translocation
● Not all mutations affect the order of amino acids but some do
● Mutagenic agents increase the rate of mutation
○ High energy ionising radiation
○ Chemicals
● Stem cells
○ Multicellular organisms are made out of specialised cells
■ Totipotent (earliest)
■ Pluripotent
■ Multipotent
■ Unipotent (latest)
○ Stem cells differentiate to become specialised cells depending upon which genes
are expressed
○ Induced pluripotent stem cells (iPs)
● Regulating transcription and translation
, ○ Transcriptional factors
■ Bind to a promoter
■ Activators
■ Repressors
○ Oestrogen effect on gene transcription
○ RNA interference (RNAi) can inhibit translation of mRNA
■ siRNA (and miRNA in plants)
■ miRNA in mammals
● Epigenetics
○ Epigenetic control
○ Epigenetic marks
○ Epigenome
○ Acetylation
■ Addition of acetyl group means chromatin is less condensed so it's easier
for transcription factors and RNA polymerase to bind and for a gene to be
transcribed
■ Removal of acetyl group means chromatin is more condensed which
makes it more difficult for a gene to be transcribed
● Deacylation involves enzyme deacetylase
○ Methylation
■ Methyl group always attaches to CpG site
■ Increased methylation of DNA switches a gene off
● Epigenetics and cancer
○ Tumours
■ Cancerous/Malignant
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 lydiashabong. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.99. You're not tied to anything after your purchase.
