Questions

Q1.
There are various ways of investigating brain structure and function.

(a)  Compare the use of computed tomography (CT) with magnetic resonance imaging (MRI) for studying brain structure.
(3)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(b)  Suggest why functional magnetic resonance imaging (fMRI) is considered better than CT for studying brain function.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(c)  The diagrams below show two MRI scans of the brain of a patient with a tumour. Scan 1 was taken before treatment was carried out, and scan 2 after treatment.

(i)  Suggest why the tumour appeared white in the scans.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(ii)  Using the information in the diagrams, describe the effect of the treatment on this tumour.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(iii)  Using the information in the diagrams, suggest two brain functions that may have improved after treatment. Give a reason for your answer.
(3)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(Total for Question = 12 marks)

Q2.
 
Schizophrenia is a disorder that affects brain structure and function and has a variety of symptoms.
The bar graph shows how the relationship to a family member suffering from schizophrenia affects the risk that the individual will also develop schizophrenia.
The percentage risk of schizophrenia in the general population is included for comparison.

(a)  Explain the difference between the percentage risks of developing schizophrenia in identical twins and non-identical twins of the same gender.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(b)  Some early studies of schizophrenia included identical twins raised in separate families.

(i)  Explain how the design of these studies allows the influence of environmental factors on the development of schizophrenia to be investigated.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(ii)  The conclusions based on these early studies of identical twins raised in separate families are said to lack validity.
Give two reasons why these studies may lack validity.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(c)  Schizophrenia has been linked to abnormally high levels of a neurotransmitter in the brain.
Explain how the action of the drugs used to treat schizophrenia may lead some patients to experience symptoms similar to those of Parkinson's disease.
(5)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 

(Total for question = 11 marks)

Q3.
 
Serotonin is found in the brain and is important in health and wellbeing.
An imbalance of serotonin can lead to problems such as depression. An individual with symptoms of depression may have low serotonin levels in the brain.
The use of drugs such as MDMA (ecstasy) can cause an imbalance of chemicals in the brain.
(i)  Describe how the use of MDMA could affect the transmission of impulses in the brain.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
(ii)  Individuals who use MDMA may develop the symptoms of depression.
Explain how the use of MDMA could result in the development of these symptoms.
(2)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 ............................................................................................................................................. 
 
(Total for question = 4 marks)

Mark Scheme

Q1.

Q2.

Q3.