Which statement provides the best evidence that the muscular system interacts with the respiratory system to carry out life processes?

a
the absorption of oxygen by sacs called alveoli shows how specialized tissues are necessary for movement of substances through the respiratory system.

b
the protection provided by the rib bones shows how the respiratory system needs hardened organs to keep it working properly.

c
the diaphragm’s movement downward to draw air into the lungs shows how muscles are necessary to bring air into the body.

d
the initiation of the breathing process by the phrenic nerves shows how neurons are necessary for blood oxygenation.

The correct statement is C The diaphragm"s movement downward to draw air into the lungs shows how muscles are necessary to bring air intto the body.

Explanation:

Diaphragm is important part of the respiratory system.During inhalation of oxygen diaphragm moves downward with the help of adjacent respiratory muscle by the same way during exhalation diaphragm moves upward to diffuse the carbon dioxide out of the body.

    Diaphragm along with respiratory muscles play an important role in proper gas exchange.

the sun d the answer is sun

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.