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 lower layer of the skin is called the dermis. This is the structural layer, the leather of the skin. It holds you together. The dermis is made up mostly of collagen and about 4% elastin fibers. Collagen provides the strength of the skin, while elastin allows it to stretch and snap back.