Answer to Question 1
Vitamin A contributes to the health of the bones. This vitamin affects the expression of genes (DNA into protein), which can affect cell development. If vitamin A is deficient, the cells that build bone may not be fully functional. This could affect the quality of the bone tissue.
Vitamin D is essential for bone health. It stimulates the small intestine to absorb more calcium from foods so that the bones can make use of the calcium. Young people who lack vitamin D during growth may have softened, misshapen bones, as is seen with rickets. Older individuals may experience softening of the bones as calcium is released from them as a result of vitamin D deficiency. This condition is known as osteomalacia.
Vitamin C is needed for the formation of collagen, the base material of bones and other connective tissues. Vitamin C deficiency, known as scurvy, leads to poorly formed connective tissue, which can cause bleeding of the gums or rashes on the skin.
Answer to Question 2
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A maneless male lion, who also has little body hair - from Tsavo East National Park, Kenya
The Body as Mapped on the Motor Cortex and Somatosensory Cortex
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