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.
[2 marks]
6 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
Two plants grow under the same bright, warm conditions. One has plentiful water; the other has dry soil and closes many stomata.
Explain how closing stomata helps the dry-soil plant but can limit its growth.
[6 marks]
6 marksHigher
Spec and skills
Original practice question
Answer and supported method checks
A town offers a vaccine against a serious droplet-spread disease. Some residents cannot receive it for medical reasons. A group argues that vaccination is purely an individual choice with no effect on other people.
Evaluate the group's claim using vaccination and transmission.
[6 marks]
6 marksHigher
Spec and skills
Original practice question
Answer and supported method checks
A researcher needs to observe chloroplast movement in living cells and examine internal membranes below the resolution limit of a light microscope.
Evaluate light and electron microscopy for these tasks.
[6 marks]
4 marksFoundation and Higher
Spec and skills
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.
