Mark Scheme (Results)
Summer 2023
Pearson Edexcel GCE
In Biology (9BIO)
Paper 3: General and Practical Principles in
BiologyEdexcel and BTEC
... [Show More] Qualifications
Edexcel and BTEC qualifications are awarded by Pearson, the UK’s largest awarding body. We
provide a wide range of qualifications including academic, vocational, occupational and specific
programmes for employers. For further information visit our qualifications websites at
www.edexcel.com or www.btec.co.uk. Alternatively, you can get in touch with us using the
details on our contact us page at www.edexcel.com/contactus.
Pearson: helping people progress, everywhere
Pearson aspires to be the world’s leading learning company. Our aim is to help everyone
progress in their lives through education. We believe in every kind of learning, for all kinds of
people, wherever they are in the world. We’ve been involved in education for over 150 years,
and by working across 70 countries, in 100 languages, we have built an international reputation
for our commitment to high standards and raising achievement through innovation in
education. Find out more about how we can help you and your students at:
www.pearson.com/uk
Summer 2023
Question Paper Log Number P71911A
Publications Code 9BIO_03_2023_MS
All the material in this publication is copyright
© Pearson Education Ltd 2023General Marking Guidance
• All candidates must receive the same
treatment. Examiners must mark the first candidate in
exactly the same way as they mark the last.
• Mark schemes should be applied positively. Candidates
must be rewarded for what they have shown they can do
rather than penalised for omissions.
• Examiners should mark according to the mark scheme
not according to their perception of where the grade
boundaries may lie.
• There is no ceiling on achievement. All marks on the mark
scheme should be used appropriately.
• All the marks on the mark scheme are designed to be
awarded. Examiners should always award full marks if
deserved, i.e. if the answer matches the mark
scheme. Examiners should also be prepared to award
zero marks if the candidate’s response is not worthy of
credit according to the mark scheme.
• Where some judgement is required, mark schemes will
provide the principles by which marks will be awarded
and exemplification may be limited.
• When examiners are in doubt regarding the application
of the mark scheme to a candidate’s response, the team
leader must be consulted.
• Crossed out work should be marked UNLESS the
candidate has replaced it with an alternative response.Question
Number Answer Additional Guidance Mark
1(a) Accept HO for OH
(1)
OH
H
OH
HQuestion
Number Answer Additional Guidance Mark
1(b) An answer that includes three of the following:
• cellulose is made up of beta glucose (monomers) but
starch is made up of alpha glucose (monomers) (1)
• cellulose contains {unbranched / straight / linear}
chains (of glucose) but starch contains branched chains
(1)
• cellulose contains 1,4 glycosidic bonds but starch
contains 1,4 and 1,6 glycosidic bonds (1)
• {inverted / flipped} glucose molecules in cellulose but
glucose molecules in same orientation in starch (1)
Piece 2 adjacent sentences only
Accept b / β and a / α
Accept cellulose contains one type of
molecule but starch contains {two types /
amylose and amylopectin}
Accept amylose is coiled but cellulose is {not
coiled / a straight chain molecule}
Accept starch contains 1,6 glycosidic bonds
but cellulose does not
Accept a diagram
(3)Question
Number Answer Additional Guidance Mark
1(c) An explanation that includes the following:
• insoluble (1)
• so does not {have an osmotic effect / affect
water potential} (1)
or
• {compact / dense / coiled / tightly packed} (1)
• so a lot can be stored in a {small / given}
space (1)
or
• (amylopectin / starch is) branched (1)
• so can be {broken down / hydrolysed} more
quickly (1)
Do not piece
Accept so cannot cross membrane and leave cell
Ignore takes up less space unqualified
Accept contains many {end branches / terminal glucose molecules}
Ignore easy / easier release
(2)
(Total for Question 1 = 6 marks [Show Less]