Question

what are hormones? what are photocrome

Answer 1

A hormone is any member of a class of signaling molecules produced by glands in multicellular organisms that are transported by the circulatory system to target distant organs to regulate physiology and behaviour.


Phytochromes are a class of photoreceptor in plants, bacteria and fungi use to detect light. They are sensitive to light in the red and far-red region of the visible spectrum and can be classed as either Type I, which are activated by far-red light, or Type II that are activated by red light.[2] Recent advances have suggested that phytochromes also act as temperature sensors, as warmer temperatures enhance their de-activation

Answer 2

Photochromic lenses may be made of glass, polycarbonate, or another plastic. They are principally used in eyeglasses that are dark in bright sunlight, but clear in lowambient light conditions. They darken significantly within about a minute of exposure to bright light, and take somewhat longer to clear.