During infancy and childhood, growth does not occur at a steady rate (Carel, ... Growth slows between 4 and 6 years old: During this time children gain 5–7 ... and the parent or caregiver should discuss this with the child's pediatrician.
In the lungs, oxygen is put into the blood and carbon dioxide is taken out of the blood during the process of breathing. After the blood gets oxygen in the lungs, it is called oxygen-rich blood.
