BIOL 1201 Lecture : My Final Notes
Document Summary
Cell signaling: direct: cells communicate with each other directly, local: paracrine and synaptic signals, distant: hormonal signals (endocrine system) Some plant processes follow a daily cycle suggesting plants have rhythms. Cell signaling regulation: cell signals regulate a wide variety of processes largely through two different mechanisms, antagonistic pairs, example: blood glucose levels. Glucagon, insulin: glucagon: stimulates the breakdown of glycogen to glucose. Insulin: stimulates the conversion of glucose to glycogen. Both produced by pancreas: negative feedback. Ions allowed to pass: number of gates, na+ channels: 2 gates, activation gate (open) Inactivation gate (close: k+ channels: 1 gate. Integration example: vertebrate eye, structures, photoreceptors (rods, cones, ganglion cells (form optic nerve, bipolar cells (connect receptors to ganglion cells, horizontal cells (connect receptors together, amacrine cells (connect ganglions together, figure 50. 17. Chemical synapses: enzymes secreted by postsynaptic membrane destroy neurotransmitters or, neurotransmitters pumped back into pre-synaptic cell (re-uptake) Depression: low levels of serotonin, treatments, ssris, zoloft, paxil, prozac, maois, nardil, parnate, emsam.
