Microscopic filtering units in the kidney are called . The artery carries blood to the kidney and branches of this artery carry this blood to the first part of the nephron, ___, ___, ___, and other substances ___, which passes the substances into the ___. As these materials pass through various sections of the tubule, substances needed by the body are and returned to blood . Excess products such as ___ and ___, some , and ___ remain in the tubule and become known as the concentrated waste liquid called ___.

b a mature ovary of a plant.

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.

i got you i did it ya know what it is just needing to fill this in for a quick task!