Core B exam questions

Question 1

A baby has the following symptoms following a children’s birthday party at a small indoor soft play area.

35 children were in attendance throughout the day, where children shared the same play area, toys and eating area.

What is the likely cause of the illness in the baby?

Answer 1

• lack of social distancing in the children at the party (1)
• inadequate sanitation of equipment and play areas (1).

Question 2

Identify one of the two stages of the body’s response to injury.

Answer 2

• involuntary inflammatory response (1)
  Note: Do not accept inflammation unqualified
• proliferation stage (1).

Question 3

In epidemiology, which one of the following best describes the difference between incidence and prevalence?

A Prevalence calculates the decline in new cases and incidence focuses on the rise of existing cases.

B Prevalence focuses on using smaller relevant data whereas incidence focuses on incidents creating data.

C Prevalence is the analysis of existing cases and incidence analyses new cases.

D Prevalence is the analysis of new cases and incidence analyses existing cases.

Answer 3

C: Prevalence is the analysis of existing cases and incidence analyses new cases.

Question 4

Identify the organelle responsible for energy release within cells and name this process.

Answer 4

• mitochondria (1).
• respiration (1) or
• aerobic respiration (1).

Question 5

An overweight 68-year-old male smoker exercises less than 30 minutes per week.

On climbing stairs, he experiences chest pains, is out of breath and feels exhausted.

Give two examples of physiological factors that are causing him to experience these symptoms.

For both physiological factors, explain why it causes these symptoms.

Answer 5

climbing stairs increases use of oxygen (1) which (the lower oxygen levels) will be
experienced as exhaustion and feeling out of breath (1).

atherosclerosis/fatty deposits in arteries (1) reducing blood supply to the heart (1)

physical activity increases the need for oxygen/blood (1) as less oxygen is available, it causes breathlessness/exhaustion (1)

Question 6

During the transcription process, DNA is transcribed into messenger RNA using a sequence of base pairs.

Identify the missing base to complete the pairs in the table below:

DNA RNA
Adenine ?
Cytosine Guanine
Guanine Cytosine
Thymine Adenine

Answer 6

Uracil

Question 7

Identify one of the two stages of the body’s response to a soft tissue injury

Answer 7

• involuntary inflammatory response (1)
• proliferation phase (1).

Question 8

Give two ways in which mechanical digestion breaks down food in the mouth

Answer 8

• teeth mechanically break food into smaller pieces (1)
• tongue will help chewing of food into a ball (bolus) (1)
• tongue will help move food to the throat and therefore stomach (1).

Question 9

Give one way in which mechanical digestion breaks down food in the stomach

Answer 9

• stomach muscles contract (peristalsis) (to aid digestion) (1).

Question 10

Which one of the following does the pH scale measure?

A Hydrogen atoms
B Hydrogen compounds
C Hydrogen ions
D Hydrogen neutrons

Answer 10

C: Hydrogen ions.

Question 11

In electro-surgery, a generator converts mains alternating current to a radio frequency.

Select the correct frequency that the generator would convert the current to.

A 50 Hz
B 100 Hz
C 500 Hz
D 1000 kHz

Answer 11

A 50 Hz

Question 12

Ultrasounds are often used to create images inside the body for monitoring an existing condition or to diagnose a condition.

Explain two limitations of using an ultrasound to diagnose a condition

Answer 12

• Ultrasound images are not as detailed as those from CT or MRI scans (1)Ultrasound cannot tell whether a tumour is cancer (1)
• Ultrasound cannot be used to diagnose conditions on the entire body as sound waves do
  not travel well through bone or air