Human Physiology Skin and Accessory Structures

Question :

The skin and accessory structures perform a variety of essential functions, such as protecting the body from invasion by microorganisms, chemicals, and other environmental factors; preventing dehydration; acting as a sensory organ; modulating body temperature and electrolyte balance, and synthesizing vitamin D.

The underlying hypodermis has important roles in storing fats, forming a cushion over underlying structures, and providing insulation from cold temperatures.

For this discussion:

. select TWO functions of the integumentary system.

. describe the physiology behind them.

. provide examples of each.

Answer :

Part1

The given video is about skin and its layers. The speaker talks about the different layers of skin. Thus, the first thing that I learned from the video is that there are many layers of skin. The outermost layer of skin is composed of entirely dead cells. The layer of skin can be categorized into three sets of layers. The first set of layers is called epidermis that is consisted of five layers. The second set of layers is called dermis that has two layers and the third set is called hypodermis or subcutaneous tissue that has only one layer. The most superficial part of the skin is epidermis that is also the topmost layer of the skin.

The epidermis comprises of five layers and the bottommost layer of the epidermis is called basal layer or stratum basale. This is the layer where human being firstly generates keratinocytes. Keratinocytes come from a protein or an intermediate filament that is known as cytokeratin. The purpose of it is to provide a skin tough outer layer. It is also a layer where rapid cell division occurs. Thus, cells are made here, and gradually they move upwards. This layer is also important because it is the layer the skin gets color from. The next layer is the stratum spinosum in which the connection between keratinocytes starts generating. It is also important to note that every layer has different types of cells. The next layer is called stratum granulosum where granules are produced. The next layer is called stratum lucidum where keratinocytes work so hard to make keratohyalin granules as well as releases lamellar bodies. The topmost layer is called stratum corneum where dead bodies go for autopsies.

Part-II

The integumentary system comprises of skin, glands, nails, hair, as well as nerves. This is also the largest organ in the body. The main function of this system is to protect the body by acting as a barrier to the outside world. It also helps in retaining body fluids, eliminating waste products, protecting against diseases, as well as regulating body temperature (Diegel et al., 2018). The two functions of the integumentary system that will be discussed are the following;

• Protecting internal living organs as well as tissues of the body

• Regulating body temperature

The skin of the body provides an anatomical barrier between the internal as well as the external environment in bodily defense. The integumentary system protects the body from physical damage by providing a thick barrier. It regulates body temperature. For example, when an individual feels too cold or too hot, the brain sends nerve impulses to the skin that can control the body temperature in different ways. If hairs are standing up, they trap more warmth. On the other hand, if they are lying flat, they trap less warmth (Pang et al., 2017). Apart from this, glands under the skin conceal sweat onto the surface of the skin to enhance heat loss by evaporating in case of high temperature. 

References 

Diegel, K. L., Danilenko, D. M., & Wojcinski, Z. W. (2018). The Integumentary System. In Fundamentals of Toxicologic Pathology (pp. 791-822). Academic Press.

Pang, V. F., Schiefer, H. B., & Beasley, V. R. (2017). Effects on the integumentary system. Trichothecene Mycotoxicosis Pathophysiologic Effects (1989), 2, 10.

2020. [online] Available at: https://www.youtube.com/watch?v=TjYbFdSY0LA&feature=youtu.be