Sclera pass. The thickness of the sclera varies from 1mm at the posterior pole to 0.3 mm just behind the rectus muscle insertions. The sclera's blood vessels are mainly on the surface. Along with the vessels of the conjunctiva (which is a thin layer covering the sclera), those in the episclera render the inflamed eye bright red. In many vertebrates, the sclera is reinforced with plates of cartilage or bone, together forming a circular structure called the sclerotic ring. In primitive fish, this ring consists of four plates, but the number is lower in many living ray-finned fishes, and much higher
Effect of spaceflight on the human body 1971, the ship's depressurization resulted in the death of the entire crew. Two other people were decompressed accidentally during space mission training programs on the ground, but both incidents were less than 5 minutes in duration, and both victims survived. In a vacuum, there is no medium for removing heat from the body by conduction or convection. Loss of heat is by radiation from the 310 K temperature of a person to the 3 K of outer space. This is a slow process, especially in a clothed person, so there is no danger of immediately freezing. Rapid evaporative cooling of