Respiratory system

Label the parts of the respiratory system.

The following is a picture taken from the inside of the windpipe. What is the function of the rings of cartilage that can be seen?

In what order does air move through the respiratory system when you inhale?

The [blank_start]alveoli[blank_end] are tiny air sacs in the lungs surrounded by tiny blood vessels called capillaries. [blank_start]Oxygen[blank_end] passes from the air sacs into the capillaries where it is taken first to the [blank_start]heart[blank_end] and then pumped to all cells in the body. [blank_start]Oxygen[blank_end] is used by our cells to release energy from food. This is called [blank_start]respiration[blank_end] and produces a waste called [blank_start]carbon dioxide[blank_end]. This is a toxic gas if it builds up in our bodies so it is transported by the blood from the cells back to the heart before finally being pumped to the lungs where it passes back into the [blank_start]alveoli[blank_end] before being [blank_start]exhaled[blank_end].