- Chargaffs rule states...
A. In humans, the amount of G and C are equal, and the amount of A and T are equal, but not in other species.
B. In prokaryotes, the amount of C and T are equal, and the amount of A and G are equal, but not in eukaryotes.
C. In any species, the amount of G and C are equal, and the amount of A and T are equal.
D. In eukaryotes, the amount of G and T are equal, and the amount of A and Care equal, but not in prokaryotes.

Option C

Explanation:

For chagarff's rule, it clearly states that DNA from any cell of any organisms be it prokaryotes or eukaryotes should have the basic 1 (purine): 1 (pyrimidine) ratio. Particularly, amount of adenine should be equal to thymine, and guanine equal to cytosine. This is in particular reference to organisms that have double stranded DNA.

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

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.