Hormones control many cell activities, so they are very important for homeostasis, and growth hormone is an important hormone that declines with aging. Given these facts, what affects cell aging among the following options: - hormones - radiation - Smoking - fat - acid - temperature - cigarettes - weather
hormones

Increasing heat causes thermal expansion, and motion helps to increase body heat. Given these facts, what causes thermal expansion among the following options: - power - Chimneys - Sun - motion - Energy. - sunlight - coal - energy
motion

Biofuel is used to produce electricity by burning, and ethanol is the most widely used biofuel today. Given these facts, what is used to produce electricity by burning among the following options: - air - heat - energy - cells - calcite - hydrogen - fire - ethanol
ethanol