The process of keeping the internal environment of the body stable by responding to changes in the external environment is known as homeostasis. Which of the following accurately describes a mechanism for
maintaining homeostasis at the cellular level? *

Passive transport, where ATP is used to facilitate the movement of molecules from
high to low concentrations.

Facilitated transport, where enzymes are used to increase the rate of solvent transfer
across a membrane.

Active transport, where the solution is pumped across a membrane to from high to
low concentrations.

Active transport, where molecules are pumped across the cell membrane against the
gradient from low to high concentration.

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.

i think it is d. objects resist changes in their state of motion.