The Circulatory System
- hemoglobin in bloodstream picks up the oxygen in the lungs and transport it to the muscles (muscle system)
Nervous system
- breathing rate changes when concentration of carbon dioxide is too high. when the concentration of CO2 increases the chemoreceptor (chemical sensitive) cells in the wall of the carotid artery and aorta sends impulses to the respiratory centre of the brain,
- nerve impulses are also sent to the respiratory centre from the stretch receptors in the lungs - the more the lungs inflate the more nerve impulses are sent to the respiratory centre
- when the respiratory centre receives these impulses it sends impulses to the diaphragm and intercostal muscles causing them to contract and making the breathing rate increase
Immune system
- Most of the respiratory system is lined with mucous membranes which contain mucosal-associated lymphoid tissue, this tissue is part of the lymphatic system which is an essential part of the immune system because it produces immune cells (e.g. Lymphocyte which is a type of white blood cell) lymphocytes just defend the body against infections and viruses.