This Paper contains 2022

AQA A LEVEL BIOLOGY Paper 3 2022 Bundle

Question Paper + Mark Scheme 2022

Section A box

Answer all questions in this section.

You are advised to spend no more than 1 hour and 15 minutes on this section.

0 1 Amino acids are used to make proteins. Table 1 shows the R groups of six different

amino acids.

Table 1

Amino acid R group

Alanine CH3

Asparagine CH2CONH2

Aspartic acid CH2COOH

Amino acid R group

Glutamic acid CH2CH2COOH

Glycine H

Serine CH2OH

0 1 . 1 Use Table 1 to identify the three different amino acids used to make the polypeptide

shown in Figure 1.

[2 marks]

Figure 1

Left amino acid

Middle amino acid

Right amino acid

Question 1 continues on the next page

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outside the

box 0 1 . 2 Table 2 shows three statements and names of four biological molecules.

Put a tick () in each box where the statement is true for the biological molecule.

[3 marks]

Table 2

Statement DNA ATP Reverse

transcriptase Phospholipid

Contains peptide

bonds

Is formed using a

condensation reaction

Is a polymer

Figure 2 represents the structure of adult human haemoglobin.

Figure 2

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outside the

box 0 1 . 3 The number of amino acids in the beta chains in Figure 2 is 3.546% greater than in

the alpha chains. Each alpha chain contains 141 amino acids.

Calculate how many amino acids there are in total in the haemoglobin molecule

shown in Figure 2. Give your answer to the nearest whole numbe