Which of these statements is true regarding ligands? A) Ligands are always a protein. B) Each individual ligand is only able to bind to one specific receptor. C) The binding of a ligand to a receptor molecule causes the receptor to change shape. D) Ligands can pass through the plasma membrane, but must bind to receptors in the nucleus or cytoplasm.

answer; atp and nadph;

i might be wrong but i think its a. let me know if i’m right and have a good rest of your day!

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.