Review Sheet Exam 2 10 21 2010 1 2 Name the and describe all the strata in the epidermis of a thin layer and The Integumentary system a thick layer Stratum Basale o Keratinocytes mitotically active producing cells for superficial layers o Melanocytes pigment in melanocytes on superficial level of keratinocytes chemical shield of nuclei in keratinocytes o Merkel cells at epidermal junctions associated with free nerve endings to form Merkel discs that act as light touch receptors Stratum Spinsum o Several layers o All connected by desmosomes cause spiny appearance o Tonofilaments present in keratinocytes and found at desmosomes intermediate filaments o Langerhan s cells epidermal dendritic cells act as macrophages to engulf and digest pathogens Stratum Granulosum o 3 5 layers o Contains two types of granules Lamellated granules contain a glycolipid which makes the skin waterproof Keratohyaline granules contain keratin tough insoluble protein makes epidermis tough and abrasive o Thin translucent dead cells only in thick skin areas thickens resistant Stratum Lucidum epidermis Stratum Corneum o Superficial 20 30 layers of dead flat cells o Cells impregnated with glycolipids and keratin to provide tough durable waterproof coat o Replaced every 3 4 weeks 3 Name and describe the two layers in the dermis Papillary o Composed of areolar connective tissue o Surface has peg like projections called dermal papillae house blood capillaries and nerve endings and Meissner s corpuscles which act as touch receptors o In thick skin the surface of the papillae are supported by mounds called Dermal Ridges which form impressions on the epidermal surface called the epidermal ridges friction ridges increased friction and enhance gripping o Pattern of epidermal ridges is genetically determined and therefore unique to an individual acts a the basis for finger printing Reticular o Composed of dense irregular connect tissue o Deeper layer accounting for 80 of the dermis o Contains the touch receptors for deep pressure called Pacinian corpuscles collagen bundles therefore heal faster o Cleavage tension lines areas of the reticular layer with less o Incisions made parallel to the cleavage lines gape less and o Striae stretch marks indicate dermal tearing replaced by slivery white scars 4 Describe the following receptors Meissner s corpuscles papillary layer of the dermis act as touch Pacinian corpuscles located in the reticular layer of the dermis and they respond to deep pressure placed on the skin Merkel discs epidermal dermal junctions act as light touch 5 Name and discuss the function of the accessory skin structures What is acid mantle All derived from the epidermis but reside in the dermis o Sweat Sudoriferous glands Two types Eccrine Secrete sweat Palm soles forehead Three million Use merocrine as mode of secretion uses exocytosis Apocrine Secretion associated with body oil odoriferous glands Use merocrine as mode of secretion uses exocytosis Specialized sweat glands Two types Ceruminous o Lining of the external ear canal o Secrete a bitter substance called cerumen ear wax o Prevents entry of foreign objects into the ear Mammary o Breasts o Secretes milk Acidic mantle prevents microbial growth on top of the skin o Sebaceous oil glands Oil glands Simple alveolar glands Found all over the body except the palms soles Secrete an oily substance called sebum into hair follicles and via pores to the surface of the skin Sebum softens and lubricates hair and skin Use holocrine as mode of secretion results in cell Whiteheads sebum accumulated in the ducts of the Blackheads popped whiteheads that result in oxidation Acne inflammation of sebaceous glands caused by death sebaceous glands and darkening bacteria o Hairs hair follicles pili Produced by cells in the matrix inside hair follicles Each hair has two regions shaft and root Shaft region exposed above the skin Root region below the skin enclosed by the hair Hair is composed of three concentric layers of follicle keratinized cells Inner medulla the core Middle cortex the largest layer Outer cuticle a single layer of overlapping cells that protects the underlying layers and to prevent hair from matting Conditioners keep the cuticle smooth to prevent matting of the hair and split ends Alopecia rate of hair loss outpaces rate of hair growth Functions of Hairs For protection hair on scalp eyelashes To provide insulation in cold weather bands of smooth muscle attached to the hair follicles called the arrector pili muscles contract pulling the hair follicles and hairs from an oblique position to an upright position resulting in dimpling of the skin referred to as goose bumps in this position a layer of air can be trapped on the surface of skin to act as an insulator to prevent heat loss from the body o Nail 6 Name and discuss the 3 types of burns such as acids Classified based on severity Tissue damage by intense heat radiation electricity and chemical o First degree burns damage is confined to only the epidermis associated with redness swelling and pain heal in three day without medical intervention Ex Sunburn o Second degree burns damage to the entire epidermis and the papillary layer of the dermis associated with blisters fluid collection at the epidermal dermal junction swelling redness and pain heal in 3 4 weeks if infection is prevented o Third degree burns damage to the entire skin damage to the entire epidermis and dermis including all nerve ending hence the burn site is not painful subjected to infections and fluid loss medical intervention involving grafting fluid protein and ion replacement are required for healing 7 Name and define the 3 major types with skin cancer Basal Cell Carcinoma involves the proliferation of stratum basale cells the least malignant and most common type of skin cancer 80 grows slowly Squamous cell carcinoma involves the cells in the stratum spinosum second most common type of skin cancer grows rapidly Melanoma proliferation of the melanocytes most aggressive type of skin cancer highly metastic and resistant to chemotherapy least common 10 21 2010 Skeletal System 1 Compare and contrast compact and spongy bone tissues Compact bone tissue Spongy bone tissue o Composed of osteons structural unit of a compact bone o Like a honeycomb composed of needle like structures called trabelculae structural units of a spongy bone 2 Name and describe the 4 structural classes of bones What are sesamoid bones Give an example of each class Long
View Full Document
Unlocking...