Question 1 Question 2 The thymus gland is remarkably crucial to the immune system since it processes lymphocytes, which fight infections in the body. The gland is vital to young adults and children as it programs lymphocytes in attacking antigens such as the viruses. Therefore, the thymus gland has a chief role in nurturing the lymphocytes through secreting a hormone. Hence, lack of the thymus gland in the immune system can lead to failure of the immune system processing lymphocytes, which help in the fight of cancerous cells and viral infections (Lavini, 2008). Therefore, there will be decreased immunity, when there is a lack of the thymus gland in the immune system. Besides, lack of the thymus gland in the immune system may affect the functions of the hormonal tissues for example, lack of the thymus gland from birth is usually associated with alterations of the adrenal gland, pituitary gland, ovaries and thyroid. Question 3 The arteries comprise of three layers, which are Tunica Interna, Tunica Media, and Tunica Adventitia. Tunica Adventitia is the outermost layer of the arteries and has collagen fibers, which are loosely woven (Wingerd, 2005). The function of the Tunica adventit