Equal masses of fat are mixed with equal lipase concentrations at 37 °C. A has large droplets at pH 3; B has large droplets at pH 8; C has small droplets at pH 8. This lipase works best near pH 8.
.1
Explain why B should digest fat faster than A.
[2 marks]
.2
Explain why C should be faster than B and relate this to bile.
[2 marks]
4 marksHigher4.3.1.3 Bacterial diseases
AQA Trilogy 8464
Spec and skills
Paper scope: B1
Spec 4.3.1.3
Original practice question
Answer and supported method checks
A clinic diagnoses gonorrhoea in a patient with pain on urination. An initial antibiotic fails; tests identify a resistant bacterial strain.
.1
Explain why an antibiotic can be appropriate for gonorrhoea but this antibiotic failed.
[2 marks]
.2
Explain how a barrier method reduces transmission and why pain relief alone does not prevent spread.
[2 marks]
4 marksFoundation and Higher4.2.2.5 Health issues
AQA Trilogy 8464
Spec and skills
Paper scope: B1
Spec 4.2.2.5
Original practice question
Answer and supported method checks
A virus damages immune cells. Patients later get frequent infections from other pathogens. Long illness prevents some patients from working or meeting friends.
.1
Explain why other infections become more frequent.
[2 marks]
.2
Suggest two links between long illness and poorer mental health.
[2 marks]
6 marksFoundation and HigherRequired practical 054.4.1.2 Rate of photosynthesis
AQA Trilogy 8464
Spec and skills
Paper scope: B1
Spec 4.4.1.2
Original practice question
Answer and supported method checks
A class plans to investigate how light intensity affects photosynthesis using pondweed, a lamp, a ruler, a water bath and a gas-collection syringe.
Plan an investigation that produces valid, repeatable rate comparisons.
[6 marks]
4 marksFoundation and HigherRequired practical 024.1.3.2 Osmosis
AQA Trilogy 8464
Spec and skills
Paper scope: B1
Spec 4.1.3.2
Original practice question
Answer and supported method checks
Plant tissue gains 4% mass at 0.20 mol/dm³ sugar and loses 4% at 0.40 mol/dm³. Assume a linear relationship between these points.
.1
Estimate the concentration giving zero net mass change.
[2 marks]
.2
Explain what zero net change means and how to improve the estimate.
