Unit 5: Hemoglobin Testing 6 Original: October 1999 Revision: September 2010 Before you learn about how to use the HemoCue machine and take blood from clients, you need to learn about anemia and the causes of anemia.
Skin has three layers: 1  The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone. 2  The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands. 3  The deeper subcutaneous tissue (hypodermis) is made of fat and connective tissue.
The skin is composed of three main layers. The deepest is the fatty subcutan eous layer that acts as a cushion against bumps and lumps and provides insulation. Directly above it is the dermis, made of strong elastic fibers and collagen.he sun's rays can break down these proteins and, eventually, the skin begins to wrinkle and sag. The subcutaneous layer, or subcutis, is a layer of fatty tissue that provides nourishment to the dermis and upper layers of skin. It also conserves body heat and cushions internal organs against trauma.