4. Why the skin gets red when it gets sunburned
Melanin, once again, is responsible for tanned skin. The nice sun-kissed color we all long for is nothing more and nothing less than the skin’s reaction to what it considers to be a UV ray attack. Melanin acts as a kind of barrier and increases its concentration, absorbing these rays to avoid irreparable damage. This is why we see ourselves looking tan after moderate exposure to the sun.
But not all types of skin produce the same amount of melanin. Sometimes the quantity produced is not enough to prevent UV rays from reaching deeper layers of our skin. In that case, those layers end up being damaged, and we call it a sunburn. Sunburns happen when the time we spend exposed to the sun, or the way in which we do it, exceeds the protective capacity of this natural barrier. Lighter skin can already burn in about 15 minutes while darker skin can be exposed to the same radiation for longer periods without anything happening to it.
5. Our skin is full of bacteria.
During your adult life, up to 1,000 different species of bacteria can be found living in your skin. These organisms, which are created by our own body, are usually good and oftentimes needed. They help fight other pathogens that can be harmful to us — and we’re exposed to them every day. But under certain conditions such as environmental factors, aging, stress, anxiety, and excessive sun exposure, those good bacteria can turn against us and cause various skin problems. Dermatitis, acne, and rosacea are among the most common issues.
6. Why we get goosebumps
You can track goosebumps back to animals. We inherited this from them as a defensive mechanism to fight cold. Every hair is connected to the skin by a tiny muscle that can be contracted. When that happens, the hair “stands up.” The more fur an animal has, the more effective the trick is. Animal fur also bristles when they feel threatened. That’s why a cat with bristly fur and an arched back, for example, looks bigger, and that can be useful when they need to scare away an enemy.
Goosebumps may also occur during times of physical exertion, even for small activities. This is because the physical exertion activates your sympathetic, or instinctual, nervous system. Sometimes, goosebumps may come up for no reason at all.