The OLFACTORY AND THE GUSTATORY SYSTEMS have receptors which die out after sometimes because of direct exposure to the environment.
The olfactory system has to do with the perception of smell while the gustatory system has to do with taste stimuli. For these two basic sense organs, their perception rate is always highest when they are newly exposed to a stimuli, after continuous exposure to the stimuli their receptors die out.
How to negative a sentence
Hemoglobin has tetrahedral structure containing four heme groups that surround a globin group.
Heme is ringlike organic compound also known as a porphyrin to which an iron atom is attached. There are four iron atoms that bind four oxygen atoms and transport them to tissues.
Answer:
Intraspecific competition
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