Proton pumps embedded in the cell membrane use ATP to move hydrogen ions across the membrane. Which of the following best describes a function of the proton pump? It decreases the pH inside the cell to prevent toxicity.
It generates a voltage across the membrane as a way to store energy.
It helps maintain homeostasis by absorbing electrical charges.
It increases the fluidity of the cell membrane as energy is used.

b would be the right answer

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint

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.