Lactase is an enzyme that is produced in the lining of the intestines. this enzyme the body speed up the breakdown of carbohydrates that are found in dairy products, such as milk, yogurt, and cheese.
which general function does lactase perform?

Lactase is the enzyme that belongs to the class of the beta galactosidase family. Lactase enzyme has the ability to hydrolyses the disaccharide sugars. Lactase are present in the lining of the small intestine.

The general function of the lactase is the digestion of the lactose sugar. The lactose sugar is present in the milk and the enzyme lactase hydrolyzes the lactose sugar into the glucose and galactose. The individual lacking the lactase enzyme are lactose intolerance and unable to digest lactose.

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.