Why do we need recycling of carbon?

Which blood cell spend most of their time in the lymphatic system?

Ascience research group is testing a new type of plant food. one trial is conducted in a controlled experiment. the data from the trial show that the plant that received the new food grew faster than the control plant. the group announces that the new plant food makes plants grow faster. what is the main weakness in this scientific claim?

What if the yeast were extremely active and produced more than 100ml gas. would you know? why/why not