Drowning

Humans can die from drowning. Why? Water enters the lungs. Theory: Breathing in richly oxygenated water and allow diffusion to occur for oxygen to get into the bloodstream. When we breathe in air, oxygen diffuses into our bloodstream and haemoglobin will bind to oxygen immediately.

Human tissue contains myoglobin, which makes it red and haemoglobin OXYGEN DEBT During exercise, the tissue will borrow oxygen from myoglobin. Hence pale face during exercise as blood taken from the head to compensate in muscles Muscles have no metabolism to convert lactic acid, hence it need to be transported to the liver to be converted to something useful for the body During panting, the body is trying to repay the oxygen debt

GAS EXCHANGE The process by which oxygen is acquired and carbon dioxide is removed. Cellular respiration creates a constant demand for oxygen and a need to eliminate carbon dioxide gas.

PROPERTIES OF GAS EXCHANGE SURFACE Large surface area to volume ratio Thin membrane moisture concentration gradient efficient transport system (circulatory system)

MUST KNOW THE CORRECT NAMES OF THE HUMAN RESPIRATORY SYSTEM MUSCLES COME IN BUNCHES so that it can function effectively