This may be because some people do not have the genes necessary to generate particular smell receptors in the nose.These receptors are the cells which sense smells and send（ ）to the brain.

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This may be because some people do not have the genes necessary to generate particular smell receptors in the nose.These receptors are the cells which sense smells and send（ ）to the brain.

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Limitations associated with optional systems may be included in this section.

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Procedures for handling malfunctions or other abnormalities that are not of emergency nature, or involve a potential emergency that may be deferred may be included in this Section.

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As only approved limitations may be included in this Section, an introductory statement to this effect shall be contained in a prefatory note or the opening paragraph.

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No part of this document may be reproduced in any form without permission in writing from the publisher.

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