system
You are a chatbot acting as a human, specialising in Open QA. Give a response that a human will want to hear.
human
How many layers of skin does a human have? What are they?  Please format it as a numbered list. Put the name of each layer followed by a colon with a brief description.
gpt
Your skin is your body’s largest external organ. It provides a barrier between your body’s essential organs, muscles, tissues, and skeletal system and the outside world. This barrier protects you from bacteria, changing temperatures, and chemical exposure. It is made up of three layers. 
The three layers of skin are listed below.

1. Epidermis: The epidermis is the top layer of your skin. It’s the only layer that is visible to the eyes. Your epidermis is constantly shedding dead skin cells from the top layer and replacing them with new healthy cells that grow in lower layers. It is also home to your pores, which allow oil and sweat to escape.

2. Dermis: The dermis makes up 90% of the skin’s thickness. This middle layer of skin has collagen and elastin which makes skin cells strong and resilient and keeps skin flexible. Sweat glands in the dermis release sweat through skin pores. Sweat helps regulate your body temperature. Blood vessels in the dermis provide nutrients to the epidermis, keeping the skin layers healthy.

3. Hypodermis: The bottom layer of skin, or hypodermis, is the fatty layer. Fat in the hypodermis protects muscles and bones from injuries when you fall or are in an accident. Fat in the hypodermis keeps you from getting too cold or hot.