Unit 4 Reflection

In this unit, we learned all about the Integumentary system and it's basic functions. The main function of this system is to protect the body from mechanical, chemical, thermal, and bacterial damage. When I think of protection for our body, the first thing I think about is the skin. The skin is composed of three layers, the first being the epidermis. The epidermis is what everyone can see since it is the part of the skin that contains melanin, a pigment for color. However, underneath the epidermis the dermis. Made up of dense connective tissue, collagen, and elastic fibers, the dermis is what provides the skin with it's toughness. Finally, there is the hypodermis, which is the deepest layer. The hypodermis is not actually a part of the skin; however, it is an anchor of the skin to underlying organs. Although the skin might be the first physical barrier we think of for protection of our body there are many more. Others include ceruminous, which is essentially the wax found in your ears. Along with the tiny hairs found in your ears, this helps to trap foreign particles and prevents unwanted bacterial from entering the body. Another source of protection is your nails. Formed from keratin, your nails help to perform everyday tasks such as grasping and manipulation small objects but they also serves as a form of protection to keep unwanted bacteria and other foreign particles away. Similar to ceruminous, mucus membranes create linings on body cavities that are open to the exterior in order to help trap and filter invaders.
Another system of defense that our body has is chemical defense. One method of chemical defense includes sebum. Sebum is an oil that is secreted by the skin to form a protective layer. Similarly, we have sweat, or perspiration. Secreted by the sweat glands, this helps us to flush microbes from the skin's surface.
The next form of non-specific protection is through anti-microbial substances, like natural killer cells. These are white blood cells that have the ability to kill viruses infected body cells or even cancer. There are also anti-microbial processes such as inflammation. Inflammation is triggered by stress due to tissue damage. This can help to prevent the spread of pathogens and promote the repair of damaged tissue. There are three stages of inflammation, vasodilation and increased permeability of blood vessels, phagocytes migrate, and then repair. Another anti-microbial process we learned about are fevers, which inhibit microbial growth and help to stimulate the production of white blood cells.
There is also specific resistance, which is effective against a single pathogen. There is cell-mediated immunity where invaders are attacked directly by the cells and are T cell driven, and then there is antibody-mediated immunity, where invaders are destroyed by antibodies and are B cell driven. T cells help by directly attacking the infected cell and some can be memory T cells that store the memory of invading antigens for years.
The last thing we learned about was cancer. Cancer can have two types of tumors, malignant and benign. Benign tumors are noncancerous and cannot spread throughout the body, while malignant tumors are cancerous and can be very dangerous and can spread throughout the body. Metastasis is the spread of cancer cells to other parts of the body and is the most advanced and worrisome stage of the progression of cancer. Some treatments of cancer include surgery, radiation, internal radiation, and chemotherapy. In order to prevent cancer, one should avoid tobacco, limit their sun exposure and most importantly know their family history.
In this unit, I learned a lot about what happens when we get sick or when our defense system needs to go into action. I was very surprised to see how many of the everyday processes we go through help us to keep pathogens out of our body. Something as simple as sweat can help us from getting sick or an infection.
From the debates, I learned a lot about some very interesting topics. From the Nature Deficit Debate, I learned the importance of going outside and some of the amazing benefits it has, such as helping veterans with PTSD. From my debate on the organ market, I learned about the pros and cons of being able to sell your organs and how it may help but also hurt us. I found the debates very interesting and I thought it was a good way to be engaged and learn something new.












I have always considered myself to be a visual learner, and after taking the VARK questionnaire, I learned I was correct. These results were exactly what I would have expected. To play into my learning style in preparation for the test, I will study by drawing out diagrams and other visuals so I can see the material in a visually appealing way. My results from the questionnaire are below.
Visual 12
Aural 1
Read/Write 5
Kinesthetic 9