Raynaud's phenomenon refers to an ailment featured by blood vessel unusuality resulting due to overactivity of the smooth muscle in the wall of arteries, causing spasms (vasospasms with constriction) of the small vessels, which supply blood to the legs, arms, feet, and hands, and sometimes the nose and ears.
Thromboangiitis obliterans, also known as Buerger's disease and vasculitis, is characterized by thrombosis and inflammation of the small and medium arteries of the feet and legs that recurs and advances in phases.
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Answer: Shale changes into Slate.
Explanation:
Shale is a sedimentary rock, formed by the deposition and compression of clay and silt.
Shale layers is buried deep into the earth through the process of deposition (i.e the laying down of rock forming material by natural entities like glaciers, wind, and water).
Temperatures and pressures rise greatly because the shale’s layers are buried. When the temperatures and pressures become higher. The shale is changed into a metamorphic rock (with dark brown streak), called Slate.
The answer is the back of the embryo.
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