BIOL 1201 Study Guide - Final Guide: Interneuron, Photoperiodism, Selegiline
Document Summary
Promotes fruit ripening, programmed cell death, leaf abscission, response to mechanical stress. Normal growth and development, xylem differentiation, pollen tube elongation. Some plants flower only when days are long (summer) or short (winter) Night length is critical for flowering and the night must be uninterrupted. Plants contain pigments called phytochromes (one part photoreceptor and the other part protein kinase: short-day, long-night plant example: At night, pfr is slowly, naturally converted to pr. Plants track time based on the accumulation of pr. A flash of light activates the protein kinase, destroying all of the pr production and resetting the night length back equal to 0: chemical signaling in animals, two majors organ systems are involved: Endocrine: hormones are secreted into the bloodstream. Nervous: neurotransmitters are secreted into synapses between neurons. Differences: the endocrine system broadcasts the signal throughout a broad area while the nervous system sends the signal directly to a target cell via neurons.
