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Wednesday 19 June 2024 – Morning
A Level Biology B (Advancing Biology)
H422/03 Practical skills in biology
Time allowed: 1 hour 30 minutes
You can use:
a scientific or graphical calculator
a ruler (cm/mm)
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
INSTRUCTIONS
Last name
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 60.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 16 pages.
ADVICE
• Read each question carefully before you start your answer.
Turn over
, 2
1
(a) ATP, DNA and tRNA are molecules that have some similarities but several differences
in structure.
The table lists structural features of ATP, DNA and tRNA.
Use ticks (✓) to indicate the structural features that are present in ATP, DNA and tRNA.
Structural feature ATP DNA tRNA
Contains adenine
Contains ribose
Has hydrogen bonds within its molecular structure
[3]
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, 3
(b) * Different methods are used to study
DNA. Outline the methods you would use
to:
• purify DNA from plant tissue by precipitation
• separate the DNA into fragments using gel electrophoresis
• visualise the DNA bands once they have been separated.
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................................................................................................................................................... [6]
Extra answer space if required.
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..........................................................................................................................................................
verified Turn over
Wednesday 19 June 2024 – Morning
A Level Biology B (Advancing Biology)
H422/03 Practical skills in biology
Time allowed: 1 hour 30 minutes
You can use:
a scientific or graphical calculator
a ruler (cm/mm)
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
INSTRUCTIONS
Last name
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 60.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 16 pages.
ADVICE
• Read each question carefully before you start your answer.
Turn over
, 2
1
(a) ATP, DNA and tRNA are molecules that have some similarities but several differences
in structure.
The table lists structural features of ATP, DNA and tRNA.
Use ticks (✓) to indicate the structural features that are present in ATP, DNA and tRNA.
Structural feature ATP DNA tRNA
Contains adenine
Contains ribose
Has hydrogen bonds within its molecular structure
[3]
verified
, 3
(b) * Different methods are used to study
DNA. Outline the methods you would use
to:
• purify DNA from plant tissue by precipitation
• separate the DNA into fragments using gel electrophoresis
• visualise the DNA bands once they have been separated.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
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..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
................................................................................................................................................... [6]
Extra answer space if required.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
verified Turn over