OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

How does adrenaline affect the liver?

1. It stimulates the liver to produce new glycogen

2. It causes the liver to break down glycogen stores

3. It increases the production of bile

4. It decreases glucose levels in the blood

The correct answer is: It causes the liver to break down glycogen stores

The correct choice indicates that adrenaline causes the liver to break down glycogen stores. Adrenaline, a hormone that is released during times of stress or excitement, plays a vital role in the body’s 'fight or flight' response. When adrenaline is released into the bloodstream, it triggers the liver to convert stored glycogen into glucose through a process known as glycogenolysis. This increase in glucose availability is crucial, as it provides an immediate source of energy for muscles and other tissues that need to respond rapidly in stressful situations. Blood glucose levels are elevated as a result, ensuring that the body has the necessary energy reserves to react effectively. The options related to stimulating the liver to produce new glycogen, increasing the production of bile, or decreasing glucose levels are not accurate representations of adrenaline's effect on the liver. Instead, adrenaline primarily facilitates the release of glucose from glycogen, aligning with its role in preparing the body for quick action.