This video we're going to continue to talk about the integumentary system as we talk about one of its main functions of thermoregulation. And so recall that the integumentary system has a lot of different functions and one of those functions is that it plays an important role in maintaining homeostasis or maintaining internal conditions despite the fact that outside conditions change. Now, thermoregulation is the process of maintaining a stable internal body temperature. Now, the integumentary system actually has 2 main methods of thermoregulation that we have numbered down below. Number 1 and number 2. The first main method is altering the diameter of blood vessels near the skin via vasoconstriction and vasodilation. And the second main method is sweating. And so moving forward in our course, we're going to talk about each of these two methods of thermoregulation in their own separate videos, starting with vasoconstriction and vasodilation. So I'll see you all in our next video.
Integumentary System: Thermoregulation - Online Tutor, Practice Problems & Exam Prep
The integumentary system regulates body temperature through two primary methods: vasoconstriction and vasodilation, and sweating. Vasoconstriction narrows blood vessels to retain heat in cold conditions, while vasodilation widens them to release heat when the body is hot. Additionally, sweating cools the body as sweat evaporates from the skin's surface. These processes are essential for maintaining homeostasis, ensuring the body can adapt to varying external temperatures effectively.
Introduction to Thermoregulation
Video transcript
Vasoconstriction & Vasodilation
Video transcript
In this video, we're going to talk about the integumentary system's first method of thermoregulation, which is vasoconstriction and vasodilation. Altering the diameter of blood vessels in the dermis of our skin, which is near the surface, actually thermoregulates the body, allowing our body to maintain internal temperature despite changes in external temperature.
The term vasoconstriction refers to blood vessels constricting, which means that those blood vessels decrease in their diameter. Vasoconstriction of blood vessels occurs when the body is cold. What helps me remember that vasoconstriction happens when the body is cold is the 'CO' in constriction reminds me of the 'CO' in cold. When blood vessels in the dermis near the surface of the skin undergo vasoconstriction, this decreases blood flow to the skin, ultimately allowing the body to retain heat under cold conditions. The reason the body can retain heat through vasoconstriction is that with a decrease in blood flow to the skin, there is less blood near the surface, radiating less heat to the external environment. We are able to retain heat by preventing heat loss to the environment through vasoconstriction.
On the other hand, vasodilation refers to blood vessels dilating or increasing in their diameter, which occurs when the body is hot, or when the temperatures are high. Vasodilation rhymes with high temperatures, which can remind you that vasodilation occurs when the body is hot. When blood vessels in the dermis near the surface of the skin undergo vasodilation, this increases blood flow to the skin. With increased blood flow, more heat can radiate from the blood to the external environment, allowing our body to cool off by facilitating heat loss to the environment.
Let's take a look at this image down below where we can start to piece things together. On the left-hand side, we're focusing on vasoconstriction, whereas on the right-hand side, we're focusing on vasodilation. Recall that vasoconstriction occurs when it's cold outside, and the blood vessels constrict. Here, the diameter of the blood vessel is very small, which means less blood rushing toward the surface of the skin and therefore less heat radiating from the blood to the external environment. Notice the minimal heat loss when vasoconstriction of the blood vessels in the dermis occurs, allowing the body to retain heat and ultimately helping to warm the body.
On the right-hand side, we're showing vasodilation, which occurs when it's hot outside and the temperatures are high, allowing the blood vessels to widen or dilate. The diameter of the blood vessel is much larger in comparison to with vasoconstriction, allowing more blood to rush toward the surface of the skin and more heat to radiate to the external environment. This facilitates heat loss to help cool off the body under hot conditions. When there's more blood rushing to the surface of your skin, it can cause your skin to turn a reddish color, responsible for the red flushing face you get when your body is overheated.
This concludes our brief lesson on the vasoconstriction and vasodilation of blood vessels in the dermis of the skin to allow for thermoregulation. We'll be able to get some practice learning this and talk more about thermoregulation via sweating as we move forward. I'll see you all in our next video.
Integumentary System: Thermoregulation Example 1
Video transcript
So here we have an example problem that says, after exercising on a hot day, Paula has a red flushed appearance on her face. What caused this? And we've got these 4 potential answer options down below. Now, option a says the heat released from sweat evaporating. Now, although it's true that Paula is probably sweating a lot after exercising on a hot day, that sweat is not going to create a red flushed appearance on her face. And so, for that reason we can eliminate answer option A. As we'll learn moving forward, sweat is a water-based solution and so it is going to be clear and colorless. And so, again, it's not going to create a red flushed appearance on her face.
Now, moving on, option B says increased oxygen levels in the blood. But when we're exercising, our muscles are actually consuming more oxygen in the blood and so it's very possible that the blood oxygen levels are actually decreased instead of increased as option B suggests. And oxygen itself is a colorless gas and the oxygen levels in the blood are not going to be enough to create the red flushed appearance on her face, and so, for that reason we can eliminate option B. So now we're between either option C or option D and what you'll notice is option C says vasoconstriction of blood vessels whereas option D says vasodilation of blood vessels. And so, recall that on a hot day when the temperatures are high our blood vessels are going to dilate. And so this tells us that vasodilation of blood vessels is going to be the correct answer. And recall that with vasoconstriction, the CO here can remind you that this occurs when it is cold outside. But again, this is a hot day so we know that it's not going to be vasoconstriction. That's why we can eliminate answer option C and indicate that option D is the correct answer to this example and that concludes this example so I'll see you all in our next video.
Given what you know about homeostasis, which type of feedback loop do you think vasoconstriction and vasodilation are classified as?
Negative feedback loop.
Positive feedback loop.
Sweating
Video transcript
In this video, we're going to talk about the integumentary system's second method of thermoregulation, which is sweating. Sweat or perspiration is a water-based solution secreted onto the surface of the skin by sweat glands when the body gets too hot. The body is actually cooled down when the sweat evaporates off the surface of the skin. Notice down below we have a diagram of the integumentary system and you can see these sweat glands throughout the dermis here. These sweat glands are exocrine glands because they secrete the sweat onto the surface of the skin. Notice here that these little bubbles you see are the sweat puddles themselves. The red lines coming off of the sweat puddles are lines that represent the evaporation of the sweat. It's when the sweat evaporates off the surface of the skin that the body is actually cooled down. Later in our course, we will talk more about sweat and sweat glands. But for now, this here concludes our video on sweating, and we'll be able to get some practice applying these concepts moving forward. I'll see you all in our next video.
What happens in the integumentary system of a person who is overheating?
Blood vessels dilate and sweat glands are inactive.
Blood vessels dilate and sweat glands are active.
Blood vessels constrict and sweat glands are inactive.
Blood vessels constrict and sweat glands are active.