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What is the function and location of the papillary layer components?

1. Papillary layer: consists of a highly vascularized areolar tissue with all of the typical cell types within it. a. This layer also contains the capillaries, lymphatic vessels, and sensory neurons that supply the surface of the skin. b. The papillary layer gets its name from the dermal papillae that project between the epidermal ridges. c. This layer nourishes and supports epidermis.

Explain how the skin functions to protect deeper tissues

1. Protection- The low pH of skin retards bacteria multiplication, this is a chemical barrier. The hard keratnized cells also provide a physical barrier. 2. Body temperature regulation- sweating etc... 3. Sensation- stimuli such as irritating chemicals, or extreme heat or cold are detected by sensors just beneath the skin. 4. Metabolic functions- synthesizes pre cursor to vitamin D, and protects you from harmful UV radiation. 5. Excretion- some nitrogen containing waste is eliminated through the skin from sweating.

What is the cause of alopecia?

Alopecia is the medical term for baldness; there are various types of alopecia, including alopecia areata. Alopecia areata is a condition that causes a person's hair to fall out. It is an autoimmune disease; that is, the person's immune system attacks their own body. In this case, their hair follicles.

What is the function and location of the apocrine gland?

An apocrine sweat gland , from Greek apo- "away" and krinein "to separate") is a sweat gland composed of a coiled secretory portion located at the junction of the dermis and subcutaneous fat, from which a straight portion inserts and secretes into the infundibular portion of the hair follicle.In humans, apocrine sweat glands are found only in certain locations of the body: the axillae (armpits), areola and nipples of the breast, ear canal, eyelids, wings of the nostril, perianal region, and some parts of the external genitalia. Modified apocrine glands include the ciliary glands in the eyelids; the ceruminous glands, which produce ear wax the mammary glands, which produce milk. The rest of the body is covered by eccrine sweat glands.

What is the function and location of the arrector pili muscle?

Arrector Pili Muscle - This is a tiny muscle that attaches to the base of a hair follicle at one end and to dermal tissue on the other end. In order to generate heat when the body is cold, the arrector pili muscles contract all at once, causing the hair to "stand up straight" on the skin.

What is the cause of athlete's foot?

Athlete's foot occurs when the tinea fungus grows on the feet. You can catch the fungus through direct contact with an infected person or by touching surfaces contaminated with the fungus. The fungus thrives in warm, moist environments and is commonly found in showers, on locker room floors and around swimming pools.

What is the cause of malignant melanoma?

Basics Malignant melanoma, while not as common as the nonmelanoma skin cancers, is the most deadly form of skin cancer. Malignant melanoma can arise from a pre-existing mole, or from normal skin. It often appears as an unusual, odd-shaped lesion, with irregular shape or color. The thicker the lesion, the greater the chances are that it has already spread (metastasized) to lymph nodes and distant sites. At this point, prospects for long-term survival tend to be poor. However, cure rates are high if the lesion is discovered and removed in its earliest stage. A variety of new treatments are currently being tested for this feared disease, which often strikes adults in the prime of life. Causes Melanoma is predominantly associated with excessive sun exposure, but can also arise in areas of the body protected from sunlight. Like all skin cancers, malignant melanoma is most common in fair-complexioned individuals who have a history of bad sunburns and chronic sun exposure. It also tends to run in some families with a recognized gene mutation, which seems to confer increased susceptibility to the disease. For unknown reasons, a small percentage of melanomas occur on areas that are normally protected from sunlight, such as the palms of the hands, the soles of the feet, or under the nails. Melanoma originates from cells that are actually supposed to protect our skin from sunlight (melanocytes). Melanoma develops from melanocytes, cells that contain melanin, the pigmented chemical that protects our skin from sunlight. Melanocytes are located in the deepest (or basal) layer of the outermost layer of the skin (epidermis). Early melanomas may grow slowly, and only on the surface of the skin for a period of months or several years. Later, lesions tend to get thicker and grow deeper into the skin. Melanoma then tends to grow aggressively, and spreads to distant sites. The cancer cells spread to lymph nodes in the area, and through the bloodstream to the liver, lungs, bones, and brain.

What is the function and location of the dermal papillae?

Bring nutrients and oxygen to hair follicles The dermal papillae are part of the uppermost layer of the dermis, the papillary dermis, Dermal papillae also play a pivotal role in hair formation, growth and cycling.

What is the cause of cold sores?

Cold sores are caused by certain strains of the herpes simplex virus (HSV). HSV-1 usually causes cold sores. HSV-2 is usually responsible for genital herpes. However, either type can cause sores in the facial area or on the genitals. Most people who are infected with the virus that causes cold sores never develop signs and symptoms.

What is the function and location of the eccrine gland secretions?

Eccrine glands function throughout life since birth. The secretion of eccrine glands is a sterile, dilute electrolyte solution with primary components of bicarbonate, potassium, and sodium chloride (NaCl). There are other components secreted such as glucose, pyruvate, lactate, cytokines, immunoglobulins, antimicrobial peptides (e.g. dermcidin), and many others. Dermcidin is a newly isolated antimicrobial peptide produced by the eccrine sweat glands.

What is the function and location of the sweat gland?

Eccrine glands have three primary functions: Thermoregulation: sweat cools the surface of the skin and reduces body temperature. Excretion: eccrine sweat gland secretion can also provide a significant excretory route for water and electrolytes. Protection: eccrine sweat gland secretion aids in preserving the skin's acid mantle, which helps protect the skin from colonization from bacteria and other pathogenic organisms. Located in the reticular layer of the dermis

What is the function and location of the eccrine gland?

Eccrine glands, sometimes called merocrine glands) are the major sweat glands of the human body, found in virtually all skin, with the highest density in palms and soles,than on the head,but much less on the trunk and the extremities.In lower mammals they are relatively sparse being found mainly on hairless areas such as foot pads. They reach their peak of development in man where they may be 200-400/sq. cm of skin surface. They produce a clear, odorless substance, consisting primarily of water and NaCl. NaCl is reabsorbed in the duct to reduce salt loss, but is dysfunctional in cystic fibrosis thus producing salty sweat. They are active in thermoregulation by providing cooling from water evaporation of sweat secreted by the glands on the body surface and emotional induced sweating (anxiety, fear, stress, and pain). The white sediment in otherwise colorless eccrine secretions is caused by evaporation that increases the concentration of salts. The odour from sweat is due to bacterial activity on the secretions of the apocrine sweat glands, a distinctly different type of sweat gland found in human skin. Eccrine glands are composed of an intraepidermal spiral duct, the "acrosyringium"; a dermal duct, comprising a straight and coiled portion; and a secretory tubule, coiled deep in the dermis or hypodermis. The eccrine gland opens out through the sweat pore. The coiled portion is formed by single layer of columnar or cuboidal epithelial cells, which are secretory in nature. The epithelial cells are interposed by the myoepithelial cells. Myoepithelial cells support the secretory epithelial cells. The duct of eccrine gland is formed by two layers of cuboidal epithelial cells. Eccrine glands are innervated by the sympathetic nervous system, primarily by cholinergic fibers whose discharge is altered primarily by changes in deep body temperature(core temperature), but by adrenergic fibers as well.The glands on palms and soles do not respond to temperature but secrete at times of emotional stress.

Explain the ABCDE rule for skin?

How to tell if your mole is benign or malignant melanoma A-Asymmetry B-Border (uneven borders is benign) C-Color (variety of colors is benign) D-Diameter (Malignant is larger) E-Evolving (If the mole changes in any way contact your doctor)

What is the cause of impetigo?

Impetigo is caused by one of two kinds of bacteria-strep (streptococcus) or staph (staphylococcus). Often these bacteria enter the body when the skin has already been irritated or injured because of other skin problems such as eczema, poison ivy, insect bites, burns, or cuts.

What is the function and location of the parietal pleura?

It is affixed to the wall of the thoracic cavity and covers the superior diaphragm surface It covers the diaphragm and lines the inner walls of the chest. This structure is a serous membrane and produces a type of serous fluid referred to as Pleural fluid. The fluid helps the surfaces of the visceral and parietal pleurae easily glide over each other when the lungs dilate and contract during respiration.

What is the function and locations of keratin?

Keratin is a family of fibrous structural proteins. Keratin is the key structural material making up the outer layer of human skin. It is the key structural component of hair and nails, and it provides the necessary strength and toughness for masticatory organs, such as the tongue and the hard palate

What is the order of epidermal layers from the outside of skin to inside (for the palms and soles of feet, and other layers)?

Layers of the epidermis: Stratum Corneum Stratum Lucidum (Only in Palms and soles) Stratum Granulosum Stratum Spinosum Stratum Basale Layers of the Dermis: Papillary Layer Reticular Layer The upper, papillary layer, contains a thin arrangement of collagen fibers. The lower, reticular layer, is thicker and made of thick collagen fibers that are arranged parallel to the surface of the skin.

What is the function and location of the fingernail component?

MATRIX Where new nail plate cells are created and the nail plate begins to form. LUNULA A bluish-white, opaque area that is visible through the nail plate. This area is the front part of the nail matrix. Sometimes, it's called the "moon." The lunula is the front part of the matrix we can see, or in other words, the visible matrix. EPONYCHIUM Living skin at the base of the nail plate that covers the matrix area. This should NOT be confused with the "cuticle". PROXIMAL FOLD OF THE EPONYCHIUM A tight band of living tissue that most people incorrectly think is their "cuticle". Since this skin dries out easily, people are quick to clip this skin believing that it's not necessary. CUTICLE A thin layer of dead tissue riding on the nail plate to form a seal between the nail plate and eponychium to prevent pathogens from infecting the matrix area. The cuticle pulls away from the underside of the eponychium and attaches tenaciously to the nail plate. The cuticle should NOT be confused with the "eponychium". NAIL PLATE Composed of hardened, flat, translucent, non-living, keratin nail cells that form a solid, protective layer over the underlying soft tissue. The nail plate should NOT be confused with the nail "bed". The average person has 50 layers of keratin cells that make up the nail plate. The thickness of your nails is determined by the size of your matrix. Not everyone's matrix is the same size. People with thin nails have a small matrix and will have less than 50 layers. People with thick nails have a large matrix and have more than 50 layers. NAIL BED The soft, pink tissue that sits underneath and supports the nail plate while it grows. The nail bed should NOT be confused with the nail "plate". HYPONYCHIUM A soft tissue seal underneath the extended "free" edge of the nail plate whose purpose is to prevent pathogens from infecting the nail bed. ONYCHODERMAL BAND A band of bunched up tissue located behind the hyponychium. This band improves the ability of the hyponychium to prevent pathogens from infecting the nail bed. The onychodermal band works in the same way as the proximal fold on the top surface of the nail. When looking at your bare nails, you can see this darker band of skin right before your nail plate leaves the nail bed to become your free edge. SOLEHORN CUTICLE A thin layer of dead tissue riding on the nail plate to form a seal between the nail plate and hyponychium to prevent pathogens from infecting the nail bed. The solehorn cuticle pulls away from the underside of the hyponychium and attaches tenaciously to the nail plate. BONE Bone supports and shapes both the nail matrix and nail bed. The flat or curved shape of your nails is determined by the shape of your fingertip bone.

What is the function and location of the melanocyte layer?

Melanocytes Listeni/mɛˈlænɵsaɪt/ are melanin-producing cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea),[1] the inner ear,[2] meninges,[3] bones,[4] and heart.[5] Melanin is the pigment primarily responsible for skin color. Once synthesised, melanin is contained in a special organelle called a melanosome and moved along arm-like structures called dendrites, so as to reach the keratinocytes.

What is the function and location of the oil gland?

Our skin has oil glands which secrete essential oils to keep it moist and soft. The moisture helps the skin in fighting against outside climate and infections.

What is the function and location of the visceral pleura?

Outer layer of the lungs Gives a smooth slippery surface to the lungs which allows it to move freely in the parietal pleura Covers the lungs closely and adheres to all the surfaces of the organ except at the hilum and along the spot where it attaches to the pulmonary ligament. It moves down into the fissures and covers the lobes.

What is the function and location of the parietal pericardium?

Parietal pericardium: The outer layer of the pericardium which is a conical sac of fibrous tissue that surrounds the heart and the roots of the great blood vessels. The pericardium has outer and inner coats. The outer coat is tough and thickened, loosely cloaks the heart, and is attached to the central part of the diaphragm and the back of the sternum (breastbone). The inner coat is double with one layer closely adherent to the heart while the other lines the inner surface of the outer coat with the intervening space being filled with fluid. This small amount of fluid, the pericardial fluid, acts as a lubricant to allow normal heart movement within the chest. The word "pericardium" means around the heart

What is the function and location of the shaft of hair?

Protects from heat and cold, alerts to the presence of a foreign entity on the skin, and protect eyes in the eyelashes

What is the cause of psoriasis?

Risk factors for psoriasis include: family history of the condition. having a viral or bacterial infection. obesity. smoking. uncontrolled stress. use of certain medications, such as those used to treat bipolar disorder and high blood pressure.

What is the cause of seborrhea?

Since this condition tends to occur in areas of heavy sebum production, it is felt that oily skin may be a factor leading to seborrheic dermatitis. In addition, it seems that many patients with seborrheic dermatitis have excessive growth of a normal skin yeast (Pityrosporum or Malassezia) in the affected areas. A skin condition that causes scaly patches and red skin, mainly on the scalp.

What is the function and location of the dermal sheath of hair?

The dermal sheath that surrounds the outside of the hair follicle contains progenitor cells that maintain and regenerate the dermal papilla, a key component for hair growth.

What is the function and location of matrix of hair?

The germinal matrix of a hair follicle is sometimes referred to as simply the "matrix" when the context of hair follicles leaves no ambiguity. However, unless the "hair follicle" is stated or is obvious from the context, the term "germinal matrix" (on its own) is unclear because it is used with reference to several regions in the body, e.g. the region of the brain with this name, and the root of the fingernail. The germinal matrix of a hair follicle is located around the papilla at the base of the bulb of the hair. It is the source of hair growth and is involved in transfering melanin to hair to give it pigmentation. During the active hair growth phase, the cells in the matrix grow quickly and differentiate (by the mitosis process of cell division), causing the hair to grow - i.e. to get

What is the function and location of the cuticle of hair?

The hair cuticle is the outermost part of the hair shaft. It is a hard shingle-like layer of overlapping cells, some five to twelve deep. It is formed from dead cells which form scales that gives the hair shaft strength and do the best job of providing protection for it. The hair cuticle is the first line of defense against all forms of damage; it acts as a protective barrier for the softer inner structure including the medulla and cortex. The cuticle is responsible for much of the mechanical strength of the hair fiber. A healthy cuticle is more than just a protective layer, as the cuticle also represents the structure that controls the water content of the fiber. Much of the shine that makes healthy hair so attractive is due to the cuticle.[ The hair cuticle is also said to be water resistant.

What is the function and location of the hair root?

The hair root is the part of the hair below the surface of the skin that includes and/or interacts with many other associated structures within the dermis and hypodermis layers of skin.

What is the function and location of the hypodermis components?

The hypodermis is the innermost and thickest layer of the skin. It invaginates into the dermis and is attached to the latter, immediately above it, by collagen and elastin fibres. It is essentially composed of a type of cells specialised in accumulating and storing fats, known as adipocytes. These cells are grouped together in lobules separated by connective tissue . 1. Abundant blood vessels that supply nutrients and waste disposal for the epidermis and dermis 2. Temperature regulation: helps to insulate the body 3. Shock absorber: it absorbs some of the force of a physical impact. 4 Fat and water storage: the pattern of fat deposition is a genetically and sexually determined. In males, it tends to be more abundant around the abdomen, while in most females it accumulates around the hips, thighs and breasts. Roughly half of the body's fat supply is stored in the hypodermis, more abundant in women generally. 5. Attachment of skin to the tissues below it-usually muscles but bone in some places. The hyposdermis loosely tethers the dermis (skin) to the structure immediately below it. This allows the skin some freedom of movement, yet keeps the skin snuggle against the body surface.

What is the function and location of the mitotic epidermal layer?

The keratinocytes divide in the skin's mitotic layer . The innermost part of the epidermis, this is made up of a single line of keratinocytes held together and to the underlying dermis by desmosomes , a sort of "press stud" structure. Each keratinocyte divides to produce two identical daughter cells. One remains static in order to divide again while the other migrates to the upper layer, the differentiation layer , where it will undergo a number of morphological and biochemical changes.

What is the function and location of the medulla of hair?

The medulla is the innermost layer of the hair shaft. This nearly invisible layer serves as the pith or marrow of the hair. Scientists are still uncertain about the exact role of the medulla, but they speculate that it is primarily an air space that is more prominent in in-pigmented (grey or white) hair.

What is the function and location of the parietal peritoneum?

The peritoneum is thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal viscera. It is composed of layer of mesothelium supported by a thin layer of connective tissue. Parietal peritoneum is that portion that lines the abdominal and pelvic cavities. Those cavities are also known as the peritoneal cavity.

What is the function and location of the visceral peritoneum?

The peritoneum is thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal viscera. It is composed of layer of mesothelium supported by a thin layer of connective tissue. Visceral peritoneum covers the external surfaces of most abdominal organs, including the intestinal tract.

What is the "rule of nines"

The rule of nines assesses the percentage of burn and is used to help guide treatment decisions including fluid resuscitation and becomes part of the guidelines to determine transfer to a burn unit. You can estimate the body surface area on an adult that has been burned by using multiples of 9.

What is the gland that causes acne and seborrhea?

The sebaceous glands are microscopic exocrine glands in the skin that secrete an oily or waxy matter, called sebum, to lubricate and waterproof the skin and hair of mammals. In humans, they are found in the greatest number on the face and scalp, and are also found on all parts of the skin except the palms of the hands and soles of the feet. The type of secretion of the sebaceous glands is referred to as holocrine. Acne is a very common problem, particularly during puberty in teenagers, and is thought to relate to an increased production of sebum due to hormonal factors. The increased production of sebum can lead to a blockage of the sebaceous gland duct. A result of this is the appearance of a comedo, (commonly called a blackhead or a whitehead) which can then result in a propensity to infection, particularly by the bacteria propionibacterium acnes. This can inflame the comedones which then change into the characteristic acne lesions.

What is the function and location of the stratum lucidum?

The stratum lucidum (Latin for "clear layer") is a thin, clear layer of dead skin cells in the epidermis named for its translucent appearance under a microscope. It is readily visible by light microscopy only in areas of thick skin, which are found on the palms of the hands and the soles of the feet.[1][2] Located between the stratum granulosum and stratum corneum layers, it is composed of three to five layers of dead, flattened keratinocytes. The keratinocytes of the stratum lucidum do not feature distinct boundaries and are filled with eleidin, an intermediate form of keratin. The thickness of the lucidum is controlled by the rate of mitosis (division) of the epidermal cells. In addition, melanosomes determine the darkness of the stratum lucidum. The cells of the stratum lucidum are flattened. They are surrounded by an oily substance that is the result of the exocytosis of lamellar bodies accumulated while the keratinocytes are moving through the stratum spinosum and stratum granulosum.

What causes sweat secretion?

The triggers of sweating:1 · Heat / temperature · Exercise · Emotions (e.g. stress, anxiety) · Hormonal changes · Food · Infection Under normal conditions our body temperature is in a state of heat balance or 'equilibrium'. If our body temperature increases due to heat from external surroundings (such as warm weather or a hot room) or internally from exercise or strenuous activity, our body will work to cool us back down by the process of sweating. The sweat on the surface of the body then evaporates, which helps to cool us down and bring our temperature back to normal. However, sweat in the armpits (also known as axillary sweating), tends not to evaporate as easily as sweating on the rest of the body, and therefore it does not play a big role in keeping us cool. Exercise Exercise causes our internal heat input to rise, triggering the body to produce sweat to cool us down and bring our body back into a state of heat equilibrium. Sweating can continue even after exercise, until the body's temperature is back to normal. Temperature regulation Under normal conditions our body temperature is in a state of heat balance or 'equilibrium'. If our body temperature increases due to heat from external surroundings (such as warm weather or a hot room) or internally from exercise or strenuous activity, our body will work to cool us back down by the process of sweating. The sweat on the surface of the body then evaporates, which helps to cool us down and bring our temperature back to normal. However, sweat in the armpits (also known as axillary sweating), tends not to evaporate as easily as sweating on the rest of the body, and therefore it does not play a big role in keeping us cool. Emotions Sweating is a normal occurrence when we experience strong emotions or stress, irrespective of temperature. This type of sweating is often referred to as 'cold sweats'. Emotions such as fear, anxiety or stress trigger the release of the hormone adrenaline and it is this rush of adrenaline which sets off a cascade of events in the body, one of which is sweating. Hormonal changes1 Puberty marks the onset of normal sweating from the apocrine glands, but other hormonal changes, such the menopause can also cause episodes of sweating. Hormonal changes during the menopause lead to a change in the body's temperature, setting off symptoms such as hot flushes [link to section](or hot flashes), night sweats [link to section] and heat intolerance. Sweating during the menopause can be so severe that it can drench clothes and bed sheets during night time. These menopausal symptoms of sweating can greatly impact a woman's quality of life. Food (gustatory sweating) Eating can cause sweat secretion as the body's temperature increases due to a rise in the body's metabolism. Some people find that hot and spicy food can cause an episode of sweating, especially on the face, scalp and neck. This happens because the substance capsaicin, which is found in spicy food, stimulates sensors in the mouth which are normally involved in thermoregulation and sweating Infection Our immune system reacts to a bacterial or viral infection by producing antibodies to fight infection and kill pathogens (bacteria or viruses). This immune system activity causes a rise in body temperature and / or a fever, which causes us to sweat. A fever goes through various stages to fight infection; profuse sweating happens at the final stages of fever when the body is working hard to cool itself down from the excess heat produced to fight the infection and bring itself back down to a normal temperature. Pheromones Sweat produced from the apocrine gland [link] is thought to contain certain chemical 'signals', known as pheromones, which aid in the communication of emotions, such as fear, anxiety or attraction. Pheromones are also implicated in attracting the opposite sex and causing women's menstrual cycles to synchronise.

What is the cause of acne?

There are different types of acne. The most common acne is the type that develops during the teen years. Puberty causes hormone levels to rise, especially testosterone. These changing hormones cause skin glands to start making more oil (sebum). Oil releases from the pores to protect the skin and keep it moist. Acne begins when oil mixes with dead cells camera.gif and clogs the skin's pores. Bacteria can grow in this mixture. And if this mixture leaks into nearby tissues, it causes swelling, redness, and pus. A common name for these raised bumps is pimples. Certain medicines, such as corticosteroids or lithium, can cause acne to develop. It isn't just teens who are affected by acne. Sometimes newborns have acne because their mothers pass hormones to them just before delivery. Acne can also appear when the stress of birth causes the baby's body to release hormones on its own. Young children and older adults also may get acne. A few conditions of the endocrine system, such as polycystic ovary syndrome and Cushing's syndrome, can lead to outbreaks of acne.

What is the function and location of melanin and tanning?

UV radiation must first be absorbed by molecules to cause any chemical change. Only that radiation absorbed by the skin can initiate a biologic response. A molecule that absorbs light is called a chromophore. These include molecules such as DNA, RNA, and proteins. After absorbing the energy of the radiation, the molecule is in an excited state. The molecule exists in this excited state for a fraction of a second before losing the energy at which time a chemical change occurs. The observable effect may be increased pigmentation of the skin or erythema. The Tanning Process To understand the tanning process one first needs to realize that the skin is comprised of several different types of cells. Each type of cell has a specific function. The cells involved primarily in the tanning process are called melanocytes. Melanocytes are located at the base of the epidermis between the epidermis and the dermis below. Melanocytes use the amino acid tyrosine to produce melanin. This melanin leaves the melanocytes and travels up through the epidermis where it reacts with the UVA and UVB radiation through a chemical reaction darkening the pigmentation of the skin. As we already know the skin consists of three layers of tissue: The epidermis or outer layer, the dermis or inner layer and the subcutaneous layer. The tanning process or increased pigmentation occurs in two phases. The first one is immediate pigment darkening (IPD). IPD is a rapid darkening of the skin which begins during exposure to UV radiation and its maximum effect is visible immediately. It is caused by a change in melanin already present in the skin. IPD is most obvious in skin where significant pigmentation already exists. It occurs after exposure to the longer wavelength of UVA or visible light. IPD may fade within minutes of small exposures or may last several days after longer exposures and blend in with delayed tanning. Delayed tanning, induced mostly by UVB exposure, is the result of increased epidermal melanin and first becomes visible 72 hours after exposure. Both UVA and UVB radiation start delayed tanning by creating an excited condition in the melanocytes which in turn releases more melanin into the skin. The degree of IPD is primarily a reflection of the person's skin type. Delayed tanning demands larger doses of both UVA and UVB for any given response.

What is the cause of basil cell carcinoma?

Ultraviolet (UV) rays from the sun or from a tanning bed are the main cause of basal cell carcinoma. When UV rays hit your skin, over time, they can damage the DNA in your skin cells. The DNA holds the code for the way these cells grow. Over time, damage to the DNA can cause cancer to form.

What is the function and location of the vernix caseosa?

Vernix is theorized to serve several purposes, including moisturizing the infant's skin, and facilitating passage through the birth canal. It serves to conserve heat and protect the delicate newborn skin from environmental stress. Vernix is also thought to have an antibacterial effect; though there is little evidence to support a chemical role of vernix in protecting the infant from infection, it may form a physical barrier to the passage of bacteria. Vernix caseosa, also known as vernix, is the waxy or cheese-like white substance found coating the skin of newborn human babies. Vernix starts developing on the baby in the womb around 18 weeks into pregnancy.

What is the function and location of skin and vitamin D production?

Vitamin D is a general term used to describe several forms of a compound with vital importance for the proper absorption of calcium in bone, as well as the maintenance of blood levels of calcium and phosphorus. When certain forms of light fall on your skin, they trigger the production of a form of the vitamin called cholecalciferol, or vitamin D3. Vitamin D Production The production of vitamin D in your skin begins with exposure to any light in the ultraviolet B wavelength. Once this light penetrates your skin, it alters the composition of a skin compound called cutaneous 7-dehydrocholesterol. This alteration results in the creation of vitamin D3. Since vitamin D can be derived in this manner as well as from outside sources, scientists do not consider it a true vitamin, Colorado State University reports. Your body cannot directly use the vitamin D3 generated in your skin, according to Colorado State University. Before it becomes biologically active, it must first travel to your liver, where it is converted into a substance called 25-hydroxycholecalciferol. This new substance then passes on to your kidneys, where it is converted a second time into a form of usable vitamin D called 1,25-hydroxycholecalciferol. These intermediate and final forms of vitamin D flow through your bloodstream with the help of a specialized carrier protein called vitamin D-binding protein. Vitamin D from food sources follows a similar conversion pathway. Sun Exposure Factors You can gain enough vitamin D to fulfill your body's needs by exposing your skin to sunlight three times each week in sessions lasting 10 to 15 minutes As an alternative to sun exposure, you can gain your regular intake of vitamin D from fortified foods and supplements that contain vitamin D, according to the Office of Dietary Supplements. Nonhuman sources of vitamin D3 include chemically converted cholesterol and irradiation of lanolin, a fatty substance derived from the sebaceous glands of wool-bearing animals, such as sheep. Supplements containing vitamin D3 may provide greater benefits than other forms of the vitamin.

What is the cause of boils?

What are the clinical features of boils? Boils present as one or more tender red spots, lumps or pustules. Careful inspection reveals that the boil is centred on a hair follicle. A boil is a deep form of bacterial folliculitis; superficial folliculitis is sometimes present at the same time. Staphylococcus aureus can be cultured from the skin lesions. If there are multiple heads, the lesion is called a "carbuncle". Large boils form abscesses, defined as an accumulation of pus within a cavity. Cellulitis may also occur, i.e. infection of the surrounding tissues, and this may cause fever and illness. Why do boils occur? Most people with boils are otherwise healthy and have good personal hygiene. They do however carry Staphylococcus aureus on the surface of their skins (staphylococcal carrier state). Why this occurs is usually not known, but it is estimated that 10-20% of the population are staphylococcal carriers. Staphylococcus aureus is most commonly carried in the nostrils, armpits, between the legs and in the cleft between the buttocks. It may be transferred to other sites from the nostrils via the finger nails. Tiny nicks or grazes or something rubbing against the skin can innoculate the bacteria into the wall of a hair follicle which is a weak point in the skin's defences. Once innoculated, the bacteria cause a boil which goes on to run its usual course of about 10 days. Although most people with boils are otherwise healthy, boils are sometimes related to immune deficiency, anaemia, diabetes or iron deficiency.

What is the cause of male pattern baldness?

What causes male pattern baldness? Hair is made in hair follicles which are like tiny pouches just under the skin surface. A hair normally grows from each follicle for about three years. It is then shed and a new hair grows from the follicle. This cycle of hair growth, shedding and new growth goes on throughout life. The following is thought to occur in men as they gradually become bald: Affected hair follicles on the scalp gradually become smaller than normal. As the follicle shrinks, each new hair is thinner than the previous one. Before falling out, each new hair grows for much less time than the normal three years or so. Eventually, all that remains is a much smaller hair follicle and a thin stump of hair that does not grow out to the skin surface. Male hormones are involved in causing these changes. The level of the main male hormone, testosterone, is normal in men with baldness. Cells in the skin of the scalp convert testosterone into another hormone called dihydrotestosterone. For reasons that are not clear, affected hair follicles become more sensitive to dihydrotestosterone, which causes the hair follicles to shrink. It is also not clear why different hair follicles are affected at different times to make the balding process gradual. It is also not clear why only scalp hairs are affected and not other areas such as the beard or armpits. The condition is hereditary (genetic). Various different genes have been shown to be involved.

Due to aging, give 4 changes that occur in skin and subcutaneous connective tissue? What is the cause of these happening?

With aging, the outer skin layer (epidermis) thins, even though the number of cell layers remains unchanged. The number of pigment-containing cells (melanocytes) decreases. The remaining melanocytes increase in size. Aging skin looks thinner, paler, and clear (translucent). Large pigmented spots (age spots, liver spots, or lentigos) may appear in sun-exposed areas. Changes in the connective tissue reduce the skin's strength and elasticity. This is known as elastosis. It is more noticeable in sun-exposed areas (solar elastosis). Elastosis produces the leathery, weather-beaten appearance common to farmers, sailors, and others who spend a large amount of time outdoors. The blood vessels of the dermis become more fragile. This leads to bruising, bleeding under the skin (often called senile purpura), cherry angiomas, and similar conditions. Sebaceous glands produce less oil as you age. Men experience a minimal decrease, usually after the age of 80. Women gradually produce less oil beginning after menopause. This can make it harder to keep the skin moist, resulting in dryness and itchiness. The subcutaneous fat layer thins so it has less insulation and padding. This increases your risk of skin injury and reduces your ability to maintain body temperature. Because you have less natural insulation, you can get hypothermia in cold weather. Some medications are absorbed by the fat layer. Losing this layer changes the way that these medications work. The sweat glands produce less sweat. This makes it harder to keep cool. Your risk for overheating or developing heat stroke increases. Growths such as skin tags, warts, rough patches (keratoses), and other blemishes are more common in older people.

What is the function and location of the visceral pericardium?

the surface of the pericardial membrane that is in direct contact with the heart. Also called epicardium. The word "pericardium" means around the heart