Anat-Histo-L-08-Skin.pdf

Anat-Histo-L-08 Anatomy & Histology Of Fascia & Skin -2 Arrangement of Skin Layers Dr Ayida Al Wahaibi , AY 2024-2025 Objectives 1. Identify the layers of skin. 2. Describe the arrangement of the layer of skin. 3. Describe skin appendages, (hair, sebaceous glan...

Anat-Histo-L-08 Anatomy & Histology Of Fascia & Skin -2 Arrangement of Skin Layers Dr Ayida Al Wahaibi , AY 2024-2025 Objectives 1. Identify the layers of skin. 2. Describe the arrangement of the layer of skin. 3. Describe skin appendages, (hair, sebaceous glands, sweat glands). 4. Differentiate between different degrees of skin burns. 5. Briefly describe the systemic complications related to skin burns. What causes the changes?  Introduction What is the functional importance of the skin? The skin and its appendages together are called the integumentary system. Appendages of the skin: – Hair – Nails – Sweat and sebaceous glands 4 4  Types of Skin https://quizlet.com /428931285/histolo gy-of-skin-diagram/ Thick skin (palm of hands, Thin skin sole of foot) 5 5  Layers Of Skin 3 layers which differ in; – function – histological appearance – embryological origin. Outer layer or epidermis.. develops from the ectoderm. Dermis.. develops from the mesoderm. Hypodermis.. loose connective tissue, binds the skin to underlying structures. What do you think the developmental origin of the hypodermis? 6 6  Layers Of Skin Source: Stanford Medicine https://www.stanfordchildrens.org/en/topic/default?id=anatomy-of-the-skin-85-P01336 7 7 Layers Of Skin: 1. Epidermis Source: https://commons.wikimedia.org/wiki/File:Structure_of_mamm 8 alian_skin_and_the_layers_typically_present_in_parchment. png 8 Layers Of Skin: 1. Epidermis Formed by Keratinized stratified squamous epithelium. Basal cell form germinal layer for production of new cell. Source: Blue Histology Source: Blue Histology 9 9  Stratum Corneum Stratum Lucidum Stratum Lucidum is frequently absent, and it's Stratum Granulosum not found in thin skin. Zones Of The Stratum Spinosum Epidermis Stratum Basale https://www.coursehero.com/study-guides/cuny- csi-ap-1/organ-level-skin-epidermis-and-dermis/ 10 10 Zones Of The Epidermis 11 11  Special Cells Of The Epidermis Keratinocyte in the stratum granulosum: Characterized by the accumulation of keratin, in a process called keratinization. Help to form a waterproof barrier that functions to prevent fluid loss from the body. https://www.chegg.com/flashcar ds/derm-fe8bee01-2865-4de4- 12 9e12-fe5bb0de6b1d/deck 12  Special Cells Of The Epidermis The superficial layers of human thick skin at high magnification, showing the deeply stained keratohyalin granule-containing cells of the granular layer (G) between the prickle cell or spinous layer (S) and the clear (or lucid, L) and cornified (C) layers above. Note that the clear layer is only translucent in unstained preparations and appears eosinophilic, as here, after staining. https://clinicalgate.com/skin-and-its-appendages/ 13 13  Special Cells Of The Epidermis Melanocytes in the stratum basale Well known for their role in skin pigmentation, and their ability to produce and distribute melanin. https://commons.wikimedia.or g/wiki/File:Blausen_0632_Mel anocyte.png https://www.chegg.com/flashcar ds/derm-fe8bee01-2865-4de4- 9e12-fe5bb0de6b1d/deck 14  Layers Of Skin: 2. Dermis Thicker layer. Consists of dense irregular connective tissue. Reach in blood vessels. 15 15  Layers Of Skin: 3. Hypodermis Beneath the two layers. Made up of loose connective tissue. Binds the skin to underlying structures. 16 16 Skin Appendages: Hair Hair Sweet glands Sebaceous Glands https://teachmeanatomy.info/the-basics/ultrastructure/skin/ 17  Skin Appendages: Hair Hair follicle: Arrector extends down pilli into the dermis (smooth and, usually, a muscles short distance that pull into the hairs hypodermis. straight). https://www.researchgate.net/figure/Anatomy-of-human-skin-Human-skin- is-organised-in-the-three-layers-epidermis-dermis_fig1_360992204 18 18  Skin Appendages: Sweat Glands When you sweat the moisture on your body evaporates and provides a cooling effect for the body. produce a watery secretion. These are coiled The duct opens tubular glands on to the skin that are found in to help control the dermis of body the skin. temperature and provide an emotional response to stimulus. https://www.researchgate.net/figure/Anatomy-of-human-skin-Human-skin- is-organised-in-the-three-layers-epidermis-dermis_fig1_360992204 19 19 Skin Appendages: Sweat Glands All sweet glands are controlled by the sympathetic nervous system … why? 20  Skin Appendages: Sebaceous Glands Found in parts of the skin where hair is present. The hair follicle and its associated sebaceous gland form a pilosebaceous unit. Produce lipid Sebaceous secretion that glands empty their secretory has limited product antibacterial (sebum) into and antifungal the upper parts of the hair activity. follicles. https://www.researchgate.net/figure/Anatomy-of-human-skin-Human-skin- is-organised-in-the-three-layers-epidermis-dermis_fig1_360992204 21 21 Skin Appendages: Sebaceous Glands Note that sebaceous glands are also found in some of the areas where no hair is present, for example, lips, oral surfaces of the cheeks and external genitalia. Clinically the sebaceous glands are important in that they are liable to infections (e.g. with the development of acne). 22 22 Skin Appendages in Histological Sections https://clinicalgate.com/skin-and-its-appendages/ 23 23 Skin Appendages in Histological Sections A sweat duct in thick skin (trichrome- stained), spiralling through the dermis and epidermis, visible most clearly in the cornified superficial layer. https://clinicalgate.com/skin-and-its-appendages/ 24 24  Skin Burns https://upload.wikimedia. org/wikipedia/commons/ First Degree 3/38/Sunburn.jpg Second Degree https://upload.wikimedi a.org/wikipedia/en/8/87 /Hand2ndburn.jpg https://upload.wiki Third Degree media.org/wikipedia /commons/7/78/8- day-old-3rd-degree- burn.jpg 25 25  Skin A superficial burn. Burns The surface of the skin is damaged, but the epidermis is still intact. First Skin able to perform its functions (control Degree temperature and protect from infection or injury). Damage extends into the dermis. Also are known as partial-thickness burns. Second Blisters are the first sign of a second-degree Degree burn. The most painful.. Why? Full-thickness burns. Causes nerve death. Third The same trouble with fluid loss, heat loss, Degree and infection that come with second-degree burns. 26 26  Reading 1. Anatomy for Dental Students, 4th edition, Section 7: Skin and Fascia. pp. 47-48. 2. Schleip et al, 2019. Fascia Is Able to Actively Contract and May Thereby Influence Musculoskeletal Dynamics: A Histochemical and Mechanographic Investigation. Front Physiol. 2019; 10: 336. 27 27