10. The skin accounts for approximately 7-8% of the body’s weight. It varies in thickness and sensitivity in different regions of the body.
11. The two principal layers of the skin are the epidermis and dermis. The hypodermisis deeper and connects the dermis to underlying organs
12. IN PERSONS WHO ARE OBESE, WHERE IS THE MAJORITY OF THEIR FAT LOCATED? A INSIDE THE PERITONEAL CAVITY B INSIDE THE DORSAL BODY CAVITY C BETWEEN THE DERMIS AND MUSCLES D INSIDE THE VENTRAL BODY CAVITY E EXTERNAL TO THE EPIDERMIS
13. Wear protective gloves when handling damaging chemicals that you don’t want absorbed into your body.
14. When hands are soaked in water, they swell up as water moves by osmosis from an area of high water concentration (the water in the sink) into an area of low water concentration (the skin cells of the hand).
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16. Dermal blood vessels supply nutrients to the dermis and to the overlying epidermis. They also help regulate body temperature.
18. Vitamin D is synthesized by some epidermal cells when they are exposed to ultraviolet (UV) light. Vitamin D is essential for the process of absorbing calcium and phosphorus from the small intestine for the synthesis of healthy bones.
19. Rickets is caused by a lack of UV light necessary for the synthesis of Vitamin D or by a dietary lack of Vitamin D
20. Siberian children getting exposed to essential UV light Small amounts of UV light are necessary for synthesis of Vitamin D
21. There is NO good reason for full-body sunbathing! Excessive UV light has many damaging effects.
22. Wrinkles in the skin are associated with age and excessive exposure to damaging ultraviolet (UV) light
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27. ACCORDING TO YOUR SUPPLEMENTAL READING, WHY ARE WOMEN IN THE NETHERLANDS MORELIKELY TO DEVELOP HUMAN PAPILLOMA VIRUS INFECTIONS IN THE MONTH OF AUGUST? A EXPOSURE TO THE PERINEUM TO UV LIGHT RAYS B SUPPRESSION OF THE IMMUNE SYSTEM C INCREASED SEXUAL ACTIVITY AT THE SEASHORE D LACK OF VITAMIN D E INCREASED INTESTINAL ABSORPTION OF CALCIUM
28. There are millions of sensory receptors and numerous blood vessels in the integumentary system.
29. The skin, through the process of perspiration, eliminates waste products such as water, salts, and urea.
30. 1 2 3 4 5 There are five layers to the epidermis on the palms, soles, and lips
31. The outermost layer, the epidermis, is 30-50 cell layers in thickness. All but the deepest layers of the epidermis are dead.
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36. The stratum basale only a single cell layer in thickness. These mitotically active cells obtain their nutrients from blood vessels in the underlying dermis. Pigmented melanocytes (which contribute to skin color) are a part of the stratum basale.
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38. Note keratinocytes, tactile (Merkel) cells, and epidermal dendritic cells. Melanocytes, which are found in the stratum basale, are not shown in this photograph.
39. We are very aware of skin color, even though it is relatively trivial relative to the entire activity and structure of the human body.
40. The stratum spinosum consists of several layers of cells that have numerous spine-like projections. There is still a limited amount of mitotic activity in this layer, so this layer, and the underlying stratum basale layer, are sometimes collectively referred to as thestratum germinativum.
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42. The stratum granulosum consists of 3-5 layers of flattened cells containing dark staining granules. The process of keratinization begins in this layer.
43. The stratum lucidum consists of 2-3 rows of clear, flat, dead cells. This layer ONLY exists in the thickened skin of the palms, soles, and in the lips (areas that deal with greater friction).
44. Fuller lips in women typically occur under the stimulus of increased estrogen released during puberty.
45. The stratum corneum consists of 20-30 layers of flattened, dead, scale-like cells (cornified cells). These dead cells flake off continuously as we travel through our day.
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49. Cornification is brought on by keratinization and the hardening, flattening process that takes place as the cells migrate to the surface. Chin with beard Hairy chest
50. WHAT LAYER IS ABSENT IN A MALE’S CERVICAL REGION? A STRATUM LUCIDUM B STRATUM GERMINATIVUM C STRATUM GRANULOSUM D SUBCUTANEOUS E STRATUM CORNEUM
51. Friction on the skin stimulates increased mitotic activity in the stratum basale
52. A callus is the result of stimulation of the stratum basale cells
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54. The colored dye must go below the stratum basale into the dermis in order to stay permanently.
56. Thick epidermis is found on the palms of the hands and soles of the feet. All five epidermal layers are present, but no hair follicles or sebaceous (oil) glands.
57. Thin epidermis covers most of the body and only has four epidermal layers (lacks stratum lucidum). It also has hair follicles and sebaceous (oil) glands.
58. Normal skin color is caused mainly by the expression of a combination of two pigments: melanin in the epidermis and hemoglobin in the dermal blood vessels. Carotene is the weakest contributor.
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61. Melanin is believed to help protect the DNA of epidermal cells from damage by harmful UV light. Read in the clinical view in the text how sunscreens protect against UV radiation.
62. Red blood cells in capillaries Hemoglobin, the iron containing pigment found inside red blood cells, gives the skin its pinkish tones.
63. The role of blood (hemoglobin) in skin color can be demonstrated by pressing on the nails. The blanching (whitening) occurs because the capillaries are compressed, which forces the blood out.
64. Carrots and many other vegetables contain carotene, which may influence skin color.
65. after before View of a man’s back before, and after, eating several large carrots with each meal for four weeks. Notice orange skin color as a result of accumulated carotene. However, for most persons, carotene is not that significant a contributor to skin color.
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68. WHICH OF THE FOLLOWING IS ASSOCIATED WITH ALBINISM AND VITILIGO? A LACK OF VITAMIN D B DEFECTIVE CELLS IN STRATUM BASALE C LACK OF CAROTENE D ANEMIA E EXPOSURE TO UV LIGHT
70. Acrocyanosis is blueness of the extremities (fingers and toes) caused by poor oxygenation of hemoglobin (formation of deoxyhemoglobin, which has a bluish tint).
79. Hemangioma, which is a congenital abnormality that results in skin discoloration due to blood vessels that proliferate. Hemangiomas are the most common childhood tumor, occurring in approximately ten percent of Caucasians (more likely in females). They are benign and most disappear by age 10.
91. Dermal blood vessels vasoconstrict to reduce the loss of heat to the outer environment. This typically causes the skin to whiten as may occur on very cold days.
93. Dermal blood vessels vasodilateto allow the elimination of heat to the outer environment. This typically occurs during exercise when the body is hot and may cause the skin to redden.
94. Skin typically becomes flushed and reddish as dermal blood vessels dilate to eliminate excess heat.
95. BLUSHING, A REDDING OF THE FACE SEEN IN PERSONS WHO ARE EMBARASSED, IS CAUSED BY WHICH OF THE FOLLOWING? A ALTERED DERMATOGLYPHIC SKIN PATTERNS IN RESPONSE TO NERVE STIMULATION B EPIDERMAL BLOOD VESSELS C VASOCONSTRICTION D FLATTENING OF DERMAL PAPILLAE E LOCALIZED INCREASE IN CIRCULATING BLOOD CELLS
96. Decubitus ulcers (bed sores) occur whenever there is continuous pressure on a body part or region.
97. Common locations where blood flow is compromised (which results in cell death) when continuous pressure is applied.
115. Read about nail disorders in the clinical view of your text
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117. ACCORDING TO YOUR NOTES AND ASSIGNED READING OF CLINICAL VIEWS IN YOUR TEXT, WHICH OF THE FOLLOWING CAN CAUSE BOTH PALLOR OF THE SKIN AND SPOON NAILS? A CHRONIC BRONCHITIS B IRON DEFICIENCY C UREMIA D FUNGAL INFECTIONS E TESTOSTERONE
125. The arrector pili muscle pulls the hair so it takes on a more straight up position
126. Contraction of arrector pili muscles fluffs the fur so to appear larger to enemies and to increase thickness ofinsulation when cold.
127. Note effect of arrector pili muscles contracting in skin of cat’s tail.
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129. Contraction of arrector pili muscles in a human’s arm (goose bumps). This achieves neither increased size to frighten enemies nor does it provide additional insulation when cold.
130. Hair aids in protection, heat retention, facial expression, sensory reception, visual identification and chemical signal dispersal
131. The skin sends important information to sensory endings (vomeronasal organ) in the nose.
135. ACCORDING TO YOUR SUPPLEMENTAL READING, WHICH OF THE FOLLOWING BEST EXPLAINS WHY WOMEN LIVING IN COLLEGE DORMITORIES OFTEN HAVE SYNCHRONIZED MENSTRUAL PERIODS? A SIMILAR WAKING AND SLEEP CYCLES B UNIFORM ENCOUNTERS WITH MALE STUDENTS AND THEIR SHED SKIN CELLS ON CAMPUS DURING PORLONGED CLASSES C ISOPROPHYL ALCOHOL IN COSMETICS D AXILLARY SECRETIONS E ESTROGENIC EFFECTS OF LANOLIN IN BODY LOTIONS
136. White hair is caused by a lack of melanin in the stratum basale of the base of the hair follicle when the hair is being formed.
137. Hair loss can be caused by dietary deficiencies, high fever, radiation, drugs, genetics, changes in hormonal levels, or aging
146. Read about acne and its treatments in the clinical view in your text
147. WHICH OF THE FOLLOWING IS MOST IMPORTANT IN MAINTAINING HOMEOSTASIS OF THE HUMAN BODY DURING THE MONTHS OF JUNE AND JULY IN LOGAN? A SUDORIFEROUS GLANDS B ARRECTOR PILI MUSCLES C ANTEBRACHIAL PILI D SEBACEOUS GLANDS E. HARDENED TRANSPARENT STRATUM CORNEUM AT DISTAL ENDS OF DIGITS
148. Burns can be caused by heat, radiation, chemicals, or by electricity. Read about types of burns and grafts in the clinical view in your text.
171. Scalded Skin Syndrome, occasionally confused with intentionally caused burns, is actually caused by the bacterium Staphylococcus aureus.
172. Aging causes the skin to thin, sag, wrinkle, more susceptible to infection, become drier, more susceptible to skin cancer, and hairs loose their pigmentation.