Answer:
Explanation:
Bones are organs composed of hard living tissue providing structural support to the body – it's scaffolding. It is a hard matrix of calcium salts deposited around protein fibers. Minerals make bone rigid and proteins (collagen) provide strength and elasticity. ... The outer layer of bone is called Cortical bone.
Answer:
The respiratory centers that control your rate of breathing are in the brainstem or medulla. The nerve cells that live within these centers automatically send signals to the diaphragm and intercostal muscles to contract and relax at regular intervals.
Protection for the head is needed in cases of direct collision sports like hockey and football. Collisions with another player or the turf may result in a concussion, thus all the helmets must possess NOCSAE certifications.
The helmet should fit comfortably around all the segments of the player's head, there should be no gaps between the head and pads. It should cover the base of the skull, the pads positioned at the back of the neck should be comfortable, and at the same time should not be uncomfortable.
The helmet should not come down over the eyes, the front edge of the helmet should be 3/4 inch or of two finger widths above the eyebrows.
