Edexcel A Level 2022 papers and
markschemes
from tyrionpapers.com
Turn over
, Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel Level 3 GCE
Time 1 hour 45 minutes
Paper
reference 9BI0/01
Biology B
Advanced
PAPER 1: Advanced Biochemistry, Microbiology and
Genetics
You must have: Total Marks
Scientific calculator, HB pencil, ruler
Instructions
• Use black ink or ball‑point pen.
• centrethe
Fill in boxes at the top of this page with your name,
number and candidate number.
• Answer all questions.
• Show your working in calculation questions and include units in your answer
where appropriate.
• Answer the questions in the spaces provided
– there may be more space than you need.
• You may use a scientific calculator.
• structure yourmarked
In questions with an asterisk (*), marks will be awarded for your ability to
answer logically, showing how the points that you make are related
or follow on from each other where appropriate.
Information
• The total mark for this paper is 90.
• – usemarks
The for each question are shown in brackets
this as a guide as to how much time to spend on each question.
Advice
• Read each question carefully before you start to answer it.
• Checkanswer
Try to every question.
• your answers if you have time at the end. Turn over
Some questions must be answered with a cross in a box . If you change your mind about an
answer, put a line through the box and then mark your new answer with a cross .
1 The pathogenic effects of bacteria can be due to the toxins they release.
(a) Endotoxins are released by Gram negative bacteria.
(i) Name one type of Gram negative bacteria that releases endotoxins.
(1)
(b) Endotoxins are usually less toxic than exotoxins.
(i) The LD50 value is the mass of the chemical per kg of body mass that would kill
half the number of rodent animals.
The LD50 value can be used to indicate how toxic a chemical is.
One endotoxin has an LD50 value of 11 ng kg–1.
The mean body mass of a group of rodents is 28 g.
Calculate the mass of endotoxin given to each rodent that would kill half of
the rodents in this group.
(1)
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 Revisionbae. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.49. You're not tied to anything after your purchase.