Correct answer: C). Cells are the basic building blocks of life but do not constitute life itself
Cell theory in a biology is a scientific theory, which is universally accepted and it states that all living organism are made up of one or more cells, cell is the building block of living thing, it also states that all cell arise from ore existing cells.
The cell theory is collection of ideas and conclusion, which were given after many years of continuous research and experiment of many scientist, which tells about the cell and how it operates.
The hormone described above is the hormone Melatonin.
Melatonin is a hormone secreted by the pineal gland in the brain, which helps regulate other hormones and maintains the body's circadian rhythm. This rhythm is an internal 24 hour clock that plays a critical role when we fall asleep and when awake. When it is dark the body releases more melatonin.
Chemoreceptor is a specialized sensory receptor cell, which responds to a chemical substance and generates a biological signal.
The type of chemoreceptor responsible for our sense of smell is called olfactory receptor. It is also known as odorant receptor, these are found in a small patch of tissue high inside the nose. These cells directly connected to the brain.
The answer is "All of the above".
