Why is a starfish a keystone species?

Mario performed an experiment to determine if photosynthesis was affected by the amount of light that a plant received. what could he have done to increase the validity of his data? reduce the number of plants. remove the 1 hour group. add a 0 hours control. measure the oxygen in liters

Which layer will become saturated first when rain falls?

What molecule contains an organisms genetic material, passed down from parents to their offspring