The brain is enclosed in a box called __________ .

A plane surface of a solid enclosed by edges is called__________.

The memberanes covering the brain are called _________ .

The double-layered membrane that encloses each lung is called ________

16. In grasses, epicotyl has a shoot apex & a few leaf primordia enclosed in a ____________ foliar structure, called as_______

The voice box is called

Human heart is enclosed in a double walled sac called