Despite what you may find in some of the less well-researched MCAT books, Human Anatomy is not an MCAT topic in the sense that you need to memorize all the spinal nerves or be prepared to label the bones of the hand. However, do take time to study anatomy where it is essential for understanding the physiology. The anatomy of the digestive system and urinary system are primary examples. For the nervous system, you don't have need to go so far as learn the intricacy of the ventricular circulation of cerebrospinal fluid, but there are definitely some things you should focus on. For example, understanding the basics of the anatomy of the hypothalamus and pituitary gland are integrally important to learning a coherent narrative of physiological function. The hypothalamus in the diencephalon region of the forebrain regulates the autonomic nervous system. By either nerve impulses or neurosecretory control, the hypothalamus regulates the posterior and anterior pituitary respectively. The hypothalamus is linked to the pituitary gland via neurons as well as the blood vessels of the hypophyseal portal system. The hypothalamus links the nervous system to the endocrine system via the pituitary gland.