March 1 6a. The immune system exhibits the critical feature of self-tolerance . Failure of self-tolerance can lead to autoimmune diseases such as multiple sclerosis. March 8 7a. Just add water, and within minutes the rehydrated tardigrades are moving about and feeding.
Biological chemistry is wet chemistry.
March 22 8a. A given chemical signal can affect different target cells within an animal differently, or it may affect different species differently. It is transported into the nucleus and attaches to certain regulatory sites along regions of the target cell s genome. March 29 9a. A contrasting view is emerging from molecular systematics and developmental genetics.