从光合作用到植物中的荷尔蒙生物合成

Plant hormones—or phytohormones—are chemical molecules that modulate one or more physiological processes of a plant. In animals, hormones are often produced in specific glands and circulated via the circulatory system. However, plants lack hormone-producing glands.

Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.

Photosynthesis is a multipart, biochemical process that occurs in plants as well as in some bacteria. It captures carbon dioxide and solar energy to produce glucose. Glucose stores chemical energy in the form of carbohydrates. The overall biochemical formula of photosynthesis is 6 CO2 + 6 H2O + Light energy → C6H12O6 + 6 O2. Photosynthesis releases oxygen into the atmosphere and is largely responsible for maintaining the Earth’s atmospheric oxygen content.

The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.

Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...

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