Epithelial cells
Your epithelial cells are the cells that make up your endothelial lining. This lining covers your internal and external surfaces, like your skin, your throat, and your organs. Epithelial cells act as a barrier against any potential threats, and they're also involved in several functions within your body: such as hearing, balance, fluid transport, and absorption.
Endothelial cells
Your endothelial cells play an integral role in your cardiovascular and immune health. They form an inner layer within your heart and line your blood vessels. They play an important role in the tightening and widening of your blood vessels. They also communicate with your immune system, influencing your immune response to potential threats.
Adipose cells
Your adipose cells – or adipocytes – make up around 25% of your body weight. The main role of these cells is to store fat (thus they are also called fat cells) so that it can be used as energy. However, they also provide protective padding for your organs and are closely involved in your body's metabolic signaling.
Photoreceptor cells
Photoreceptor cells are found in the retinas of your eyes. These cells are sensitive to light and allow you to see. There are two types of photoreceptor cells: one type (rod cells) helps you to see when there's limited light. The other (cone cells) are less sensitive to light but help you see in color.
Muscle cells
Also known as myocytes, your muscle cells live within your muscle tissue and organs. One of their central roles is within your heart, where they help to regulate heartbeat contractions. These cells are also what enable your muscles to contract when you perform everyday movements like lifting heavy objects.