A) Both members of a human couple know that they are carriers of the galactosemia allele, a recessive metabolic disorder. None of their three children have the disease, but any of them may be a carrier. The couple would like to have a fourth child, but they are worried that the child would very likely have the disease since the first three do not. If the couple came to you with their worries, what would you tell them?
b) Would it remove any of the uncertainty in their prediction if they could find out from genetic tests whether their first three children are carriers of the disease? Why or why not?

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

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.