Answer:
helps ecosystem
Explanation:
provides oxygen, clear water and air, water treatment and the list goes on
Answer: Adaptation
species adapt to their environment
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.
In evolutionary biology, phylogenetic trees are used to exhibit and illustrate the evolutionary relationships of two or more organisms, and identify the origins of life altogether. To achieve this, there are three methods of classification which are phonetics, cladistics, and taxonomic groups.
