Answer:
A <u><em>receptor</em></u> is a protein that recognizes and responds to a signal.
Explanation:
A receptor is a protein molecule present on the cells on which the signalling molecules can bind and generate a physiological response. Some receptor molecules can also respond to Sun and light. Each type of cell has specific receptors molecules and hence can respond to specific signals. The receptor molecules hence tend to receive signals for a cell. Molecules such as hormones bind to the receptors.
a specialized cell, group of cells, or organ of endothelial origin that selectively removes materials from the blood, concentrates or alters them, and secretes them for further use in the body or for elimination from the body — compare endocrine gland, exocrine gland.
Answer:
A. City A because there are no pollution sources upstream.
Explanation:
Water pollution is th contamination of water. There are many means through which water is contaminated such as industrial waste, agricultural waste and domestic waste et-cetra.
City A and City B get water from sunset lake and moth lake which have factories (industrial waste) and farmland (agricultural waste) nearby them, which are responsible for the contamination of river water. due to this cities can recieve contaminated water which can affect their health.
But the quality of water in City A will be best than that of City B because according to the image, City A do not have nay upstream soooooource of pollution, as factories and farmland are located at downstream.
Hence, the correct option is A.