Why is caffeine used for heart rate experiments

According to the cladogram, which organisms have roundworms as a common ancestor?

What controls activities within a eukaryotic cell?

50 points! which of the following is an inference? a burning candle is extinguished when it is covered with a jar. the candle burns longer than expected in a jar that has a plant in it. a plant lives longer than expected in a jar that has a burning candle. there is more oxygen in the jar because there is a plant in it.