The thymus is positioned in the upper chest cavity above the heart. Thymus. The thymus gland is the main organ of the lymphatic system. Located in the upper chest region, the primary function of this gland is to promote the development of specific cells of the immune system called T lymphocytes. T lymphocytes or T-cells are white blood cells that protect against foreign organisms (bacteria and viruses) that have managed to infect body cells.
How long does it take for the Earth to rotate on its own axis ? The time it takes the Earth to rotate once is called a day (24 hours). The actual rotation time is a little less, about 23 hours and 56 minutes. Why do we have Day and Night?
Earth's rotation is the rotation of the planet Earth around its own axis.The Earth rotates from the west towards east. As viewed from North Star or polestar Polaris, the Earth turns counter-clockwise.arth's movement along its nearly circular orbit while it is rotating once around its axis requires that Earth rotate slightly more than once relative to the fixed stars before the mean Sun can pass overhead again, even though it rotates only once (360Â°) relative to the mean Sun.