Vesicles: -are transport compartments that can move particles into or out of a cell
-are surrounded by plasma membranes
-O are created by and are part of the endomembrane system or are created at the cellular membrane
-all of these
-O none of these

23

all of these

Explanation:

Certain molecules like proteins and lipids are synthesized by organnelles in a cell. These molecules are transported by small membrane enclosed sacs in a cell called VESICLES.

Vesicles are small enclosures surrounded by a membrane made of lipid bilayer. This membrane separates them from the cytoplasm of the cell. They function as transport compartments that move particles in and out of the cell.

Vesicles are produced by some organnelles that make-up the Endomembrane system like Endoplasmic Reticulum, Golgi apparatus etc. while other vesicles are created as a result of endocytosis by the cell membrane. Vesicles can serve as secretory vesicles or transport vesicles etc.

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.