18 MCQ practice problems on biological molecules. Select an answer, submit, and review the
explanation. Questions follow A-Level examination style (AQA/OCR/Edexcel) and cover carbohydrates,
lipids, proteins, nucleic acids, enzymes, and biochemical tests.
Practice Questions
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What type of bond joins two glucose molecules to form maltose?
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Which polysaccharide is composed of beta-glucose with beta-1,4-glycosidic bonds and is not digestible by humans?
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Starch is a mixture of two polysaccharides. What are they and how do their structures differ?
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Which test is used to identify the presence of lipids in a sample?
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In a triglyceride, what type of bond is formed between a fatty acid and glycerol?
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Phospholipids are essential components of cell membranes.
How does the structure of a phospholipid differ from that of a triglyceride?
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The primary structure of a protein is determined by:
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Which type of bond is NOT involved
in maintaining the tertiary structure of a protein?
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Haemoglobin is an
example of which level of protein structure?
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Which nitrogenous base is found in RNA but NOT in DNA?
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DNA replication is described as semi-conservative. What does this mean?
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A DNA molecule
has 20% adenine. What percentage of cytosine does it contain?
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Which statement correctly describes the induced fit model of enzyme action?
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A competitive inhibitor is most similar in structure to which
component of the enzyme-substrate complex?
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At very high temperatures, enzyme activity decreases because:
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A positive Benedict's test for reducing sugars produces
which colour change?
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To test for non-reducing sugars, the sample must first be treated with:
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Which
biochemical test would you use to distinguish between a solution of amino acids and a solution of
proteins?