Consider two cells, A and B. Both are approximately spherical, but cell A is a bacterium with a diameter of only about 1 µm, while the diameter of the eukaryotic cell B is about 10 µm. Recall that the plasma membrane in the eukaryotic cell comprises only about 2% of the total cell membrane. True or False: Cell A has a higher ratio of total cell membrane to volume.

False

Explanation: Cell A is bacterium, prokaryotic while cell B is eukaryotic. Eukaryotic cells are bigger cells than prokaryotic cells thus the internal volume enlarge and the total cell membrane expands. Therefore, the ratio of total cell membrane to volume of cell A is not higher than that of the ratio of total cell membrane to volume of cell B.

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.