The Soviet Union duplicated its dual-launch feat with Vostok 5 and Vostok 6 (June 16, 1963). This time they launched the first woman (also the first civilian), Valentina Tereshkova, into space on Vostok 6. Launching a woman was reportedly Korolev's idea, and it was accomplished purely for propaganda value.
Lumen: A luminous term referring to the channel within a tube such as a blood vessel or to the cavity within a hollow organ such as the intestine. Lumen is a luminous term because it is Latin for light, including the light that comes through a window. When a hollow organ is cut across, you can see light through the space that has been opened. So the word lumen came to mean this space.
Skin is the largest organ compose of dermis and epidermis. skin, nail, hair are the part of intergumentary system. Skin is the largest organ compose of dermis and epidermis. The skin is the major organ of the integumentary system. Other parts of the integumentary system in humans include the hair and nails. Integument system is the largest organ of the body. It is derived from Ectoderm of the embryo.