As food passes through the GI tract, it mixes with digestive juices, causing large molecules of food to break down into smaller molecules. The body then absorbs these smaller molecules through the walls of the small intestine into the bloodstream, which delivers them to the rest of the body.
Answer:
Sternocleidomastoid, pectoralis minor, scalenes
Explanation:
During normal inhalation, contraction of the diaphragm and the contraction of external intercostals expands the chest cavity. The increased volume of the thoracic cavity results in reduced alveolar pressure than the atmospheric pressure to facilitate the flow of air into the lungs in response to the pressure gradient.
During deep inhalation as it occurs when running up the stairs, the accessory muscles of inhalation also participate to increase the volume of the chest cavity. The contraction of scalene and sternocleidomastoid muscles increase the volume of the chest cavity further to create a greater drop in alveolar pressure.
During forceful inhalation, the sternocleidomastoid muscles serve to elevate the sternum, the scalene muscles serve to elevate the first two ribs while the pectoralis minor elevate the third through fifth ribs.
Cutting down trees results in loss of habitat for many animals in the wild, because over 70% of animals that live on land live in trees! Cutting down trees can also reduce our oxygen.
