The center which controls respiratory activities the mammalian brain is the

A student trying to find out the order in which organisms appear on a cleared plot is studying one of the following

An organism X lives entirely on the waste products in another organism Y. In this association X is a

The tips of some rice seedlings were cut off while some were left intact. Both were covered with a container which had not only one small hole to allow light through. After twenty-four hours it was observed that