The cylinders in this experiment represent a 24-hour period. The light area represents light periods during a 24-hr. period and the dark area represents dark periods during a 24-hr. period. The critical length of dark vs. light periods for flowering is depicted by the dotted line. Note that some plants are flowering and some are not flowering. Study the results of this experiment on photoperiodism and flowering to determine whether the following statements are true or false.
-A hormone is produced in small amounts in a tissue,and it causes a physiological action within that same tissue soon after its production.
Definitions:
Intracellular Signal
A form of communication within cells where signals are transmitted to elicit a specific response.
Pituitary Dwarfism
A condition characterized by abnormally short stature caused by insufficient production of growth hormone by the pituitary gland.
Hyposecretion
Abnormally reduced output of a secreted material. Compare with hypersecretion.
Growth Hormone
A hormone produced by the pituitary gland that stimulates growth, cell reproduction, and cell regeneration in humans and other animals.
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