How does this Overheating Alarm Circuit Work? Picture included? I was wondering how respectively of the components contribute to it working....

I was wondering how respectively of the components contribute to it working. Please state what each point has to jump through. Look at the picture circuit included. Best answer gets 10points
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Have you ever planted Mesclun Salad Mix or...
Answers:    The thermistor is the hose down temperature sensor. The 15K inconsistent sets the reference height (i.e. temperature at which to trigger). It would support to know what the op-amp (analogue integrated component) was. An LM339 comparator would engineer sense so that it triggers cleanly when the temperature exceeds the hint level. The XOR takings decides whether the alarm is on beneath the trigger point of the op-amp or under the quotation voltage i.e. hot or cold. The 555 is a timer which is configured as an oscillator which is controlled by the output of the XOR gate. The RC (10K x 100uF) constant is probably a bit illustrious to produce a decent alarm signal. T=RC or practically 1M x 1uF=1 second. It's more potential to be a ticking noise to some extent than an alarm tone.