Integumentary system

• It consists of the skin, hair, glands, and nails. 


  Integumentary system
• Integument means - 


  covering
• It is composed of stratified squamous epithelium and connective tissue. 


  Integumentary system
• Give the 5 function of integumentary system


  Protection, Sensation, Vitamin D, Thermoregulation, Extretion
• Epidermis consists of stratified squamous epithelium with five layers: stratum basale, spinosum, granulosum, lucidum, corneum.
• Skin has three layers: epidermis (outermost), dermis (middle layer), hypodermis/subcutaneous tissue (deepest).
• The epidermis is made up of several layers of cells that are constantly being replaced by new ones.
• The dermis contains blood vessels, nerves, sweat glands, oil glands, and hair follicles.
• Most superficial layers

  Sloughed
• Transformation of stratum basale cells into stratum corneum cells


  Keratinization
• Skin is the largest organ in the human body and is part of the integumentary system, crucial for homeostasis by helping maintain internal body temperature, fluid balance, protecting internal structures and organs, and producing Vitamin D
• The integumentary system includes skin and has layers like the epidermis, which consists of different layers such as the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale
• Keratinocytes in the epidermis produce keratin, a protein that makes cells water-resistant and tough, with cornified cells at the top layer being hardened, flattened, and full of keratin
• The dermis, below the epidermis, contains blood vessels, sweat glands, hair follicles, and nerves, with collagen providing support and elastin giving elasticity, and scars can form in the dermis if cuts reach this layer
• The hypodermis, under the dermis, connects the skin to bone and muscle tissue, containing adipose tissue for insulation, and accessory structures like sweat glands, sebaceous glands, hair follicles, and nails are part of the integumentary system
• Sweat glands help regulate body temperature by cooling the body, while blood vessels in the dermis dilate to release heat or constrict to conserve heat, and sebaceous glands produce oil to waterproof the skin and hair
• Hair follicles in the dermis have cells that rapidly divide to produce hair, made of keratin, and nails, made of dead keratinocytes, grow from cells at the nail root that frequently undergo mitosis
• Skin cancer can arise from malfunctioning integumentary cells, like basal cells leading to basal cell carcinoma, melanocytes causing melanoma, and Merkel cells resulting in Merkel cell carcinoma, emphasizing the importance of understanding the integumentary system for treatment
• Burns can affect different layers of the skin, with first-degree burns isolated to the epidermis, second-degree burns affecting the epidermis and part of the dermis, third-degree burns impacting the epidermis and all of the dermis, and fourth-degree burns extending beyond these layers to affect bones and muscles
• Significant burns can compromise skin functions like fluid maintenance and protection, making the skin vulnerable to infections, requiring extensive knowledge of the integumentary system for treatment and restoration of its functions