Dryer blower housing and blower wheel assembly. If the dryer takes too long to dryer or is noisy then the blower wheel could be damaged and require replacement.
Dryer high-limit thermostat, L260-70F. If the dryer overheats, this high-limit thermostat will cut off the power to the heating element. If the high-limit thermostat has blown, the dryer won't heat.
Dryer drum drive motor with pulley for drum belt and reverse threads for blower wheel.
Dryer thermistor. This thermistor should read approximately 50,000 (50K) Ohms of resistance at 77 degrees Fahrenheit. *Note that it is not in the heating circuit so it likely will not be the cause of a dryer heating problem. It can however effect cycle times or cause a fault if defective.
Dryer lint screen at door opening. Proper air flow is critical to dryer operation so the filter should be cleaned before every load. Replace the filter if it has any tears or rips in it.