Unit 4 kicks off our study of all the body systems. Previously we have built our background in biochemistry, general anatomical knowledge and directions, as well as histology of the human body. The study of all the bodies system will draw from this information and it will not go away, in fact it will get more and more intricate because we will be adding to the information that we have covered. Please always review your notes from previous units to help with your understanding of the human body. The Integumentary System is a fascinating and wonderful network of organs, glands, inorganic molecules working together to keep your body protected and in a state of homeostasis.