Chap 5 Integumentary System

• skin is an organ
• Cyanosis is bluish color of the skin due to deoxygenated hemoglobin
• Melanocyes are cells that make melanin in the epidermis
• Keratin is protein produced by keratinocytes to protect against abrasion
• Langerhans cells are macrophages (phagocytic cells) found in the epidermis. They protect against toxins, microbes, and other pathogens
• Stratum basale is the deepest cell layer of the epidermis where rapid mitosis of skin cells occurs
• Stratum corneum is the superficial layer of the epidermis containing dead keratinocytes
• Epidermis and dermis are the two basic layers of the skin
• The vascular layer of the skin is the dermis
• The hypodermis is the layer of areolar and adipose tissue found directly below the skin
• Papillary and reticular are two layers of the dermis
• tissue of the papillary layer is areolar
• Tissue of the reticular layer of the skin is dense irregular connective tissue
• Vitiligo is a condition where part of the epidermis is unable to make melanin creating a patch (or more) of white skin
• Albinism is a condition where there is a complete inability to make melanin
• Carotene is an orange pigment that accumulates in the stratum corneum
• Part of the hair above the skin is the shaft
• Part of the hair below the skin is the root
• Part of the hair that contains cells that form new hair is the matrix
• Nerve network around the hair root is the hair plexus
• Holocrine is a type of glandular secretion in sebaceous oil glands
• Merocrine is a type of exocrine secretion found in sweat gland of the head, neck, and palms
• Arrector pili is smooth muscle that runs between a hair follicle and the epidermis
• Ceruminous glands are exocrine glands found in the external auditory canal that produce wax
• Keratin is a protein that comprises hair and nails
• Termination of rapid cell mitosis when cells touch each other is contact inhibition
• collagen repair that extends above and beyond the borders of the wound in the skin is a keloid scar
• Skin cancer that often remains localized is the basal cell carcinoma
• First degree burn involves only the epidermis
• Second degree burn involves both the dermis and epidermis and leads to blistering
• Vitamin D is responsible for calcium absorption from food
• Layer of the skin where hemoglobin is found is the dermis
• Product of sebaceous glands that inhibits bacterial growth on the skin sebum
• The integument is made up of

  •cutaneous membrane *skin*

  •keratinized stratified squamous epithelium

  •areolar underneath

  •accessory structures
• Functions of the skin is to protect underlying tissues and organs, excrete salts, water, and organic waste (glands),

  receptors for nerve endings, synthesizes vitamin D for absorption of calcium, blood flow regulation, & detects touch, pressure, pain, and temperature
• For blood flow regulation:

  Cold- blood vessels constrict

  Hot- blood vessels dilate
• Outter epidermis contains epithelial tissues and inner dermis contains connective tissues
• The integumentary system includes both the skin and its derivatives (sweat glands, hair, nails)
• What type of epithelium does the skin contain?

  stratified squamous
• Thin skin can be found in places like the eyelid, lips, and genital regions