The Hypodermis - Online Tutor, Practice Problems & Exam Prep

The hypodermis, or subcutaneous layer, lies beneath the dermis and is primarily composed of adipose tissue, which contains adipocytes that store triglycerides. This layer anchors the skin to underlying tissues, acts as a shock absorber, and reduces heat loss, helping to maintain body warmth. It is vascular, containing numerous blood vessels, and also includes areolar connective tissue. Understanding the hypodermis is crucial for grasping the integumentary system's structure and function, emphasizing its role in insulation and protection.

The Hypodermis

In this video, we're going to begin our lesson on the hypodermis. The hypodermis is also referred to as the subcutaneous layer. It actually lies deep to the dermis, which means that it lies underneath the dermis. It's important to note that the hypodermis or subcutaneous layer is not technically part of the skin. The root "hypo" and the root "sub" are both roots that mean below.

The hypodermis lies below the dermis, and the subcutaneous layer lies below the cutaneous membrane, or below the skin. The hypodermis or the subcutaneous layer is composed mostly of adipose tissue, which is a type of loose connective tissue that is made up of adipocytes or fat cells that store fats or triglycerides. It also contains areolar connective tissue as well, which is another type of loose connective tissue. The hypodermis or subcutaneous layer actually anchors the cutaneous membrane, or anchors the skin to the underlying tissues.

It also acts as a shock absorber and an insulator that reduces heat loss. It helps to keep the body warm. Let's take a look at our image down below, and notice on the left-hand side we have the diagram of the integumentary system. Notice that the only layer that is colored is the hypodermis, or the subcutaneous layer, which is at the bottom here in yellow. It has lots of blood vessels running through it, so it is a vascular layer.

Zooming in here, notice that this yellow zoom-in represents the adipose tissue found in the hypodermis. Over here in this pink block, what we have is the areolar connective tissue that is also found in the hypodermis. In terms of the functions of the hypodermis, it is going to anchor the skin to underlying tissues. Notice we have this anchor here to remind you of that. It is also going to act as a shock absorber, absorbing shocks and helping to protect the tissues that lie underneath. It also is going to reduce heat loss to help keep us warm under cold conditions.

This here concludes our brief lesson on the hypodermis, and we'll be able to get some practice applying these concepts moving forward. I'll see you all in our next video.

The Hypodermis Example 1

So here we have an example problem that asks, why does the body store excess fat in the hypodermis? And we've got these four potential answer options down below. Now option a says, it helps the body self-insulate. And recall from our previous lesson videos that this is actually true. Storing excess fat in the hypodermis can allow the body to retain heat.

And people that have more fat in the hypodermis usually have an easier time staying warm in colder conditions. Now option b says it acts as a shock absorber to protect internal organs. Now again, adipose tissue found in the hypodermis can create a cushion, and that cushion can allow protecting organs that may lie underneath. And so option b is also true. Now option c says, it acts as an energy reserve.

And of course, we know from our previous lesson videos that again, this is true as well. That the fat molecules can actually be used as an energy source when they're broken up and released into the blood. And so this can happen specifically when carbohydrate resources are low, the body will turn to using the fat resources as energy sources. And so because options a, b, and c are all true, this means that option d, all of the above, is the correct answer to this example problem. So that concludes this example, and I'll see you all in our next video.

Elderly people have less subcutaneous fat than younger people. Which of these is something they experience due to having a thinner hypodermis?

• A. They aren't as physically strong.
• B. They are more sensitive to the cold.
• C. Their skin is tougher.
• D. Their stratum corneum sheds faster.

Here’s what students ask on this topic:

What is the hypodermis and where is it located?

The hypodermis, also known as the subcutaneous layer, is a layer of tissue that lies beneath the dermis. It is not technically part of the skin but is crucial for its function. The hypodermis is primarily composed of adipose tissue, which contains adipocytes that store triglycerides, and areolar connective tissue. This layer anchors the skin to underlying tissues, acts as a shock absorber, and reduces heat loss, helping to maintain body warmth. It is also vascular, containing numerous blood vessels.

What are the main functions of the hypodermis?

The hypodermis serves several important functions. Firstly, it anchors the skin to the underlying tissues, providing structural support. Secondly, it acts as a shock absorber, protecting the tissues beneath from mechanical damage. Thirdly, the hypodermis helps to reduce heat loss, acting as an insulator to maintain body warmth. Additionally, it stores energy in the form of triglycerides within adipocytes and contains blood vessels that supply nutrients and oxygen to the skin.

What types of tissues are found in the hypodermis?

The hypodermis is primarily composed of two types of loose connective tissues: adipose tissue and areolar connective tissue. Adipose tissue contains adipocytes, which are fat cells that store triglycerides. This tissue is crucial for energy storage, insulation, and cushioning. Areolar connective tissue, on the other hand, provides a flexible and supportive matrix that helps to anchor the skin to underlying structures. Both types of tissues contribute to the hypodermis's role in protection, insulation, and structural support.

Is the hypodermis considered part of the skin?

No, the hypodermis is not technically considered part of the skin. The skin is composed of two main layers: the epidermis and the dermis. The hypodermis, also known as the subcutaneous layer, lies beneath the dermis. Despite not being part of the skin, the hypodermis plays a crucial role in supporting the skin's functions by anchoring it to underlying tissues, acting as a shock absorber, and providing insulation to reduce heat loss.

How does the hypodermis contribute to body temperature regulation?

The hypodermis contributes to body temperature regulation primarily through its insulating properties. The adipose tissue within the hypodermis contains fat cells that store triglycerides, which act as an insulator to reduce heat loss from the body. By minimizing heat loss, the hypodermis helps to maintain a stable internal body temperature, especially in cold conditions. Additionally, the blood vessels within the hypodermis can constrict or dilate to regulate blood flow and heat distribution, further aiding in temperature regulation.