Rennet, the stomach contents of an unweaned animal; also, the membrane lining the stomach. The word rennet also refers to preparations that contain the enzyme rennin and that are used in curdling milk. The chief source of rennet is the fourth stomach of young calves. Rennet is used in making cheese, junket, and medicinal preparations. It is also used to coagulate casein (a milk protein) in making plastics.
What? You've never heard of a narwhal? Well, it's a cold-water-dwelling, deep-diving, vocalizing, halibut-munching wonder with its very own ivory crown. Did we mention its crazy tusk?
The skua is a seabird of Arctic and Antarctic regions. The skua (also called great skua)is nearly two feet (60 cm) long.