Search over 10,000 free study notes

The human gas exchange system includes the trachea, the bronchioles and the alveoli. During inhalation (breathing in) the diaphragm contracts and the external intercostal muscles contract. This increases ...

A reflex arc is made up of a receptor (which detects a stimulus), a sensory neurone, a relay neurone, a motor neurone and an effector (which brings about a respon...

Stimulus - receptor - sensory neuron - (dorsal) spinal cord - (ventral) spinal cord - motor neuron - muscle/effector - response

The high CO2 rate is detected by chemoreceptors in the aorta. The chemoreceptors send impulses to the medulla in the brain. The medulla then sends impulses along sympathetic neurons to the sinoatrial node...

The mitochondria is an organelle important for aerobic respiration. This is a process which uses glucose and oxygen to produce adenosine triphosphate, carbon dioxide and water. ATP is a molecule needed to...