The Treg cell destroys the Tc or Th cell rather than the Cell presenting self antigen because the Treg cell needs to: destroy T cells with receptors that respond to self-antigen. avoid reacting itself to self-antigen passed along by the Cell presenting self-antigen. destroy the self antigen, and it must destroy the cell in order to do this. preserve the cell in the middle that is presenting self-antigen.

answer by yourhope:

hi! : )

in which structure in the nucleus are ribosomes made?

b) nucleolus!

: )

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.

the answer is d. none of the above