Most skin tumors are benign
•Cause of cancer is unknown, but probably due to overexposure to ultraviolet radiation in the sunlight
•Threemain types of skin cancer :
•Basal cell carcinoma
•The most common type of skin tumor; usually benign.
•Cells of stratum basale are affected , they cannot form keratin and begin to invade into the dermis.
•Surgical removal (given that early detection is done) is 99% successful .
Squamous Cell Carcinoma
•arises form keratinocytes in stratum spinosum .
•mostly in the scalp , ears , or hands.
•grows and migrates rapidly.
•early detection is critical for successful treatment.
Malignant Melanoma –most dangerous
•cancer of the melanocyets in stratum basale.
•only 5% of all skin cancer , but the frequency is increasing.
•grow and migrates extremely rapidly .
•usually deadly.
Burns biology
First degree burns: only the epidermis is damaged with redness and swelling .
•Second degree burns: epidermis & upper region of dermis is involved. There is Redness, swelling, and blisters.
•Third degree burns: all layers of skin burned (most severe). Skin graft is necessary to repair. Skin looks cherry red or blacken
•Second degree burns: epidermis & upper region of dermis is involved. There is Redness, swelling, and blisters.
•Third degree burns: all layers of skin burned (most severe). Skin graft is necessary to repair. Skin looks cherry red or blacken
Telencephelon
- The teleoncephelon consist of the cerebral hemisphere, basal nuclei and olfactory bulb.
- In primitive vertebrates, the cerebral hemisphere are mainly involved with olfaction and related motor responses.
- ın higher vertebrates the gray matter of the cerebral hemisferes, except for the basal ganglia is moved to the surface, forming the cerebral cortex.
- In mammals, the cortect forms the majority of the cerebral hemispheres.
- The cortext has convulated surface and many neurons.
The integumentary system summary
Skin: The skin is the most important organ of the body.
Epidermis: are keratinized and dead cells that make the skin waterproof
Dermis: The sweat glands are present in this layer that collect waters and waste products from the blood stream. The hair roots are also present in this layer that help in the growth of hair.
Subcutaneous Layer: body temperature is also maintained within this layer by insulating the body to the temperature fluctuations.
Thermoregulation: with evaporation of the sweat and regulation of the blood flow to the dermis.
Sensations: The cutaneous sensations like touch, pressure, vibration, pain, cold are felt by the skin.
Protection: The protective barrier of the skin helps prevent diseases, infections, dehydration, etc.
Production of Vitamin D: helps in the production of vitamin D
Hair: functions of the hair include protection and sensation to light touch. The hair is made of dead, keratinized cells that are bound together with the extracellular proteins.
Nails: functions : is to help in grasping and holding things. The nails act as counter force and help increase the sensitivity of the fingertip.
Sweat Glands: that have an opening through the skin pores, help in excretion of waste matters from the circulatory system.
Epidermis: are keratinized and dead cells that make the skin waterproof
Dermis: The sweat glands are present in this layer that collect waters and waste products from the blood stream. The hair roots are also present in this layer that help in the growth of hair.
Subcutaneous Layer: body temperature is also maintained within this layer by insulating the body to the temperature fluctuations.
Thermoregulation: with evaporation of the sweat and regulation of the blood flow to the dermis.
Sensations: The cutaneous sensations like touch, pressure, vibration, pain, cold are felt by the skin.
Protection: The protective barrier of the skin helps prevent diseases, infections, dehydration, etc.
Production of Vitamin D: helps in the production of vitamin D
Hair: functions of the hair include protection and sensation to light touch. The hair is made of dead, keratinized cells that are bound together with the extracellular proteins.
Nails: functions : is to help in grasping and holding things. The nails act as counter force and help increase the sensitivity of the fingertip.
Sweat Glands: that have an opening through the skin pores, help in excretion of waste matters from the circulatory system.
Modes of hormone delivery
Endocrine: most common, classical mode, hormones delivered to target cells by blood.
Paracrine: hormone released diffuses to its target cells through immediate extracellular space. Blood is not directly involved in the delivery.
Neuroendocrine: hormone is produced and released by a neuron., delivered to target cells by blood.
Autocrine: hormone released feeds-back on the cell of origin, again without entering blood circulation.
HORMONE TARGET CELL SPECIFICITY
Only target cells, or cells that have specific receptors, will respond to the hormone’s presence. The strength of this response will depend on:
-blood levels of the hormone. – the relative numbers of receptors for that hormone on or in the target cells.
The affinity (or strength of interactions) of the hormone and the receptor.
Half-life onset and duration of hormone activity..
The affinity of hormones to their specific receptors is typically very high. The actual concentration of a circulating hormone in blood at any time reflects. – its rate of release – the speed of its inactiviation and removal from the body.
The half –life is the time required for the hormone to loose half of its original effectiveness(or drop to half of its orginal concentration)
The time required for hormone effects to take place varies greatly, from almost immediate responses to hours or even days.
In addition, some hormones are produced in an inactive form and must be activated in the target cells before exerting cellular responses.
In terms of duration of hormone action, it ranges from about 20 minutes to several hours, depending on the hormone.
CONTROL OF HORMONE RELEASE:
The synthesis and secretion of most hormones are usually regulated by negative feedback systems. As hormone levels rise, they stimulate target organ responses. These in turn, inhibit further hormone release. The stimuli that induce endocrine glands to synthesize and release hormones belong to one of the following major types.
Humoral
Neural
Hormonal
The endocrine system works closely with the nervous system to maintain and steady state of the body.the functions of hormones. Endocrin gland is ductless gland. Target issue. Chemical structure of hormones: protein, peptide, aminoacid derived and steroid hormones. Pheromones
Paracrine: hormone released diffuses to its target cells through immediate extracellular space. Blood is not directly involved in the delivery.
Neuroendocrine: hormone is produced and released by a neuron., delivered to target cells by blood.
Autocrine: hormone released feeds-back on the cell of origin, again without entering blood circulation.
HORMONE TARGET CELL SPECIFICITY
Only target cells, or cells that have specific receptors, will respond to the hormone’s presence. The strength of this response will depend on:
-blood levels of the hormone. – the relative numbers of receptors for that hormone on or in the target cells.
The affinity (or strength of interactions) of the hormone and the receptor.
Half-life onset and duration of hormone activity..
The affinity of hormones to their specific receptors is typically very high. The actual concentration of a circulating hormone in blood at any time reflects. – its rate of release – the speed of its inactiviation and removal from the body.
The half –life is the time required for the hormone to loose half of its original effectiveness(or drop to half of its orginal concentration)
The time required for hormone effects to take place varies greatly, from almost immediate responses to hours or even days.
In addition, some hormones are produced in an inactive form and must be activated in the target cells before exerting cellular responses.
In terms of duration of hormone action, it ranges from about 20 minutes to several hours, depending on the hormone.
CONTROL OF HORMONE RELEASE:
The synthesis and secretion of most hormones are usually regulated by negative feedback systems. As hormone levels rise, they stimulate target organ responses. These in turn, inhibit further hormone release. The stimuli that induce endocrine glands to synthesize and release hormones belong to one of the following major types.
Humoral
Neural
Hormonal
The endocrine system works closely with the nervous system to maintain and steady state of the body.the functions of hormones. Endocrin gland is ductless gland. Target issue. Chemical structure of hormones: protein, peptide, aminoacid derived and steroid hormones. Pheromones
intergumentary system videos and parts
Another Video of the Integumentary System, again these are some study notes & pictures to share with classmates who may benefit from them. Video is very nice and good details.
Integumentary System video
intergumentary system video and very simple integumentary system clip. very usefull for students and learners. Basic integumentary system parts explaining in this video.
The Integumentary System song
very good song about intergumentary system :) integumentary system video song ..
the skin
The skin is an important sense organ, and as such includes a number of nerves that are mainly in the dermis, with a few reaching the epidermis. Nerves carry impulses to and from hair muscles, sweat glands, and blood vessels, and receive messages from touch, temperature, and pain receptors. Some nerve endings are specialized such as sensory receptors that detect external stimuli. The nerve endings in the dermal papillae are known as Meissner's corpuscles, which detect light touch, such as a pat, or the feel of clothing on the skin. Pacinian corpuscles, located in the deeper dermis, are stimulated by stronger pressure on the skin. Receptors near hair roots detect displacement of the skin hairs by stimuli such as touch or wind. Bare nerve endings throughout the skin report information to the brain about temperature change (both heat and cold), texture, pressure, and trauma.
skin color
Skin color: Skin color results from the presence of melanin, carotene (yellow to orange pigment), and underlying blood reflected through skin. Melanin keeps excessive ultraviolet rays from burning the skin. Exposure to sunlight causes the skin to produce more melanin, causing suntan, a temporary change in skin color. Melanin-rich cells continually move toward the surface and then they are sloughed.
Integumentary System Structure and Function
Integumentary System Structure and Function video.Brief overview of the major structures and functions of the Integumentary System .
Human skin video
The Human Skin Animation Video from youtube. Integumentary system's important part is : human skin and in this youtube video you learn great usefull informations about human skin.
Functions of integumentary system
Integumentary system's main functions are below :
The integumentary system has lots of different functions, it:
Protects the body’s internal organs
Protects the body against bacteria
Protects the body from dehydration
Protects the body against sunburns
Stores water, fat, and vitamin D
The integumentary system has lots of different functions, it:
Protects the body’s internal organs
Protects the body against bacteria
Protects the body from dehydration
Protects the body against sunburns
Stores water, fat, and vitamin D
hair care tips
Caring for your hair and some tips
The most important thing is to keep their hair clean. Some people wash their hair every day, but others do it once or twice a week. That depends on the type of hair you have and where activities in which you are involved, such as exercise or swim.
When you wash your hair, use a mild shampoo and lukewarm water. Apply shampoo and massage with the fingertips, rather than nails, to make foam. You can use a conditioner or a shampoo that already contains. The conditioner helps untangle the hair and leave it soft and silky. But according to the type of hair, it may also be able to crush a lot and leave it oily. Rinse your hair with plenty of clean water. Secale gently with a towel and use a wide-tooth comb to untangle.
Try either your hair, either when wet or dry, brushing or combing carefully. Do not try pulling of desenredarte knots strong and they do not use a pony tail or braids too tight. You can irritate the scalp. And if you're using rizadores or hair dryer, be careful and ask an adult to help, if needed. If not careful, you can burn.
Here we give you a tip to showcase a beautiful hair: Follow a healthy diet. It sounds weird, but it is not. A diet rich in nutrients helps your body to look beautiful from the inside out!
The most important thing is to keep their hair clean. Some people wash their hair every day, but others do it once or twice a week. That depends on the type of hair you have and where activities in which you are involved, such as exercise or swim.
When you wash your hair, use a mild shampoo and lukewarm water. Apply shampoo and massage with the fingertips, rather than nails, to make foam. You can use a conditioner or a shampoo that already contains. The conditioner helps untangle the hair and leave it soft and silky. But according to the type of hair, it may also be able to crush a lot and leave it oily. Rinse your hair with plenty of clean water. Secale gently with a towel and use a wide-tooth comb to untangle.
Try either your hair, either when wet or dry, brushing or combing carefully. Do not try pulling of desenredarte knots strong and they do not use a pony tail or braids too tight. You can irritate the scalp. And if you're using rizadores or hair dryer, be careful and ask an adult to help, if needed. If not careful, you can burn.
Here we give you a tip to showcase a beautiful hair: Follow a healthy diet. It sounds weird, but it is not. A diet rich in nutrients helps your body to look beautiful from the inside out!
The variety of hair color
What kind of hair you have? ¿Black and wavy?, Blond and Lazio? Or some other combination? The color of the hair is given melanin, the substance that gives color to the skin. The more clear is the hair, you have less melanin. A person with black or brown hair has a lot more melanin than a hair blond or red. As people get older, decreases the amount of melanin and therefore begin to exit the gray hairs.
Usually, the skin color of a person is in agreement with the color of his hair. For example, most of the blond have light skin, while people with darker skin is brown or black hair. And do not forget the genes (the genes inherited from your parents): usually the color of the hair is determined by the color of the hair of one or both parents.
Hair follicles play a key role in determining the type of hair. Some hair follicles are structured in a way that produces wavy hair, while others generate hair Lazio. Follicles also determine whether your hair is thick or thin.
Usually, the skin color of a person is in agreement with the color of his hair. For example, most of the blond have light skin, while people with darker skin is brown or black hair. And do not forget the genes (the genes inherited from your parents): usually the color of the hair is determined by the color of the hair of one or both parents.
Hair follicles play a key role in determining the type of hair. Some hair follicles are structured in a way that produces wavy hair, while others generate hair Lazio. Follicles also determine whether your hair is thick or thin.
Where does your hair?
The hair always grows through the skin in the same way, no matter where it comes out (of your head, arm or ankle). Start at the root capillaries beneath the skin, where cells are grouped to form keratin (the protein from being formed nails). The root is within a follicle, which is a kind of small tube into the skin.
The hair grows from the root, leaves the follicle and goes through the skin, making it visible. The small blood vessels that are at the base of each follicle feed the roots of the hair to permit their growth. But once the hair emerge from the surface of the skin, the cells that form it are no longer alive. The cells of one of the hairs that you see in your body are dead. That's why when you cut your hair does not hurt us.
Virtually every hair follicle is connected to a Sebaceous gland. These sebaceous glands produce a substance, tallow, which gives the skin a shiny appearance and protects making it water resistant. Sometimes, for example during puberty, these glands can produce too much sebum (fat), which causes the hair of a person is oily. If that's the case, it is time to wash your hair!
What took the wind!
You have more than 100,000 hairs on your scalp, but every day many of them you fall. Every day, you lose about 50 to 100 hairs. This happens while you wash your hair, you comb, brush or just while you're immobile. But do not worry, constantly grow new hair to replace those that are going to fall.
Every hair on your scalp grows for about 2 to 6 years. Then, resting for a few months and finally falls. It replaced a hair again, it starts to grow in the hair follicle. This cycle of growth, rest, fall and replacement to maintain an adequate amount of hair on your head.
The hair grows from the root, leaves the follicle and goes through the skin, making it visible. The small blood vessels that are at the base of each follicle feed the roots of the hair to permit their growth. But once the hair emerge from the surface of the skin, the cells that form it are no longer alive. The cells of one of the hairs that you see in your body are dead. That's why when you cut your hair does not hurt us.
Virtually every hair follicle is connected to a Sebaceous gland. These sebaceous glands produce a substance, tallow, which gives the skin a shiny appearance and protects making it water resistant. Sometimes, for example during puberty, these glands can produce too much sebum (fat), which causes the hair of a person is oily. If that's the case, it is time to wash your hair!
What took the wind!
You have more than 100,000 hairs on your scalp, but every day many of them you fall. Every day, you lose about 50 to 100 hairs. This happens while you wash your hair, you comb, brush or just while you're immobile. But do not worry, constantly grow new hair to replace those that are going to fall.
Every hair on your scalp grows for about 2 to 6 years. Then, resting for a few months and finally falls. It replaced a hair again, it starts to grow in the hair follicle. This cycle of growth, rest, fall and replacement to maintain an adequate amount of hair on your head.
hairs biology
The "hair" is not just that you have hair on the head. You have "hair" (and hair) in almost all parts of the body. (The places where you have no hair are the lips, the palms and soles).
Most of the hair that you have in your body is easy to see, such as the eyebrows, head, arms or legs. But the hair you have on, for example, the cheeks of the face is almost invisible. Depending on the location, hair fulfills different functions. The hair that you have in your head keeps the body heat of this and gives some protection against your skull blows. Eyelashes protect your eyes by reducing the amount of light and dust that can penetrate them; and eyebrows protect the eyes of sweat that can drip on your forehead.
Most of the hair that you have in your body is easy to see, such as the eyebrows, head, arms or legs. But the hair you have on, for example, the cheeks of the face is almost invisible. Depending on the location, hair fulfills different functions. The hair that you have in your head keeps the body heat of this and gives some protection against your skull blows. Eyelashes protect your eyes by reducing the amount of light and dust that can penetrate them; and eyebrows protect the eyes of sweat that can drip on your forehead.
Integument
The Integumente are an integral part of the plant seeds of seed plants. There are Hüllschichten which encircle the Nucellus. After fertilization, the Integumente to Testa.
They leave a small opening, the Mikropyle freely through which the scar on the subject with the pollen in the pollen tube fertilization hindurchwächst.
They leave a small opening, the Mikropyle freely through which the scar on the subject with the pollen in the pollen tube fertilization hindurchwächst.
NAILS
nThese plates of highly keratinized cells are analogous to, but harder than, the stratum corneum.
A. Nail Development: The formation of the nails is similar to that of hair, but involves produc ing plates rather than cylinders. At the end of the third month of embryonic development, a narrow plate of epidermis on the dorsal surface of the terminal phalanges invades the underlying dermis of each finger and toe. This invasion continues proximally, forming a furrow called the nail groove. Epithelial cells beneath the groove proliferate to form the nail matrix, whose composition and function are similar to those of the hair's germinal matrix. Proliferation in the nail matrix pushes the upper cells toward the surface. These cells differentiate, becoming highly keratinized to form the nail plate. The plate is gradually pushed out of the groove by further cell proliferation and differentiation in the nail matrix. The growing plate slides distally on the dorsal surface of the digit. The epidermis over which it slides becomes the nail bed.
B. Nail Complex Structure: The nail plate (or nail) consists of 2 parts: the nail body (the visible part of the nail) and the nail root--(the part hidden in the nail groove). The nail and its supporting structure are surrounded by papillary dermis. The nail matrix is a thickened region of epidermis containing proliferating cells in the layer that directly contacts the dermis, and keratinizing cells between this basal layer and the nail plate. The nail matrix surrounds the root and extends beyond the nail groove. The nail bed lies beneath the nail body, distal to the nail matrix. It consists of only the deeper epidermal strata, for which the nail serves as a stratum corneum. The eponychium (or cuticle) is a thick keratinized layer extending from the upper surface of the nail groove over the most proximal part of the nail body. The hyponychium is a local thickening of the stratum corneum underlying the free (distal) end of the tail. The lunula is the whitish, opaque, crescent-shaped region on the proximal nail body, adjacent to the nail groove. Its distal border corresponds roughly to the underlying nail matrix
A. Nail Development: The formation of the nails is similar to that of hair, but involves produc ing plates rather than cylinders. At the end of the third month of embryonic development, a narrow plate of epidermis on the dorsal surface of the terminal phalanges invades the underlying dermis of each finger and toe. This invasion continues proximally, forming a furrow called the nail groove. Epithelial cells beneath the groove proliferate to form the nail matrix, whose composition and function are similar to those of the hair's germinal matrix. Proliferation in the nail matrix pushes the upper cells toward the surface. These cells differentiate, becoming highly keratinized to form the nail plate. The plate is gradually pushed out of the groove by further cell proliferation and differentiation in the nail matrix. The growing plate slides distally on the dorsal surface of the digit. The epidermis over which it slides becomes the nail bed.
B. Nail Complex Structure: The nail plate (or nail) consists of 2 parts: the nail body (the visible part of the nail) and the nail root--(the part hidden in the nail groove). The nail and its supporting structure are surrounded by papillary dermis. The nail matrix is a thickened region of epidermis containing proliferating cells in the layer that directly contacts the dermis, and keratinizing cells between this basal layer and the nail plate. The nail matrix surrounds the root and extends beyond the nail groove. The nail bed lies beneath the nail body, distal to the nail matrix. It consists of only the deeper epidermal strata, for which the nail serves as a stratum corneum. The eponychium (or cuticle) is a thick keratinized layer extending from the upper surface of the nail groove over the most proximal part of the nail body. The hyponychium is a local thickening of the stratum corneum underlying the free (distal) end of the tail. The lunula is the whitish, opaque, crescent-shaped region on the proximal nail body, adjacent to the nail groove. Its distal border corresponds roughly to the underlying nail matrix
Apocrine Sweat Glands
nB. Apocrine Sweat Glands
n1. Distribution. Less numerous than the eccrine type, these glands occur mainly in the axilla, pubic and anal regions, and the areolae of the breasts. 2. Structure. Apocrine sweat glands are also simple coiled tubular glands, but are generally larger than eccrine glands. a. Ducts. These coiled ducts are lined with low cuboidal epithelium and open into hair follicles . b. Secretory portions. Coiled and embedded in the dermis, each has a wide lumen lined by cuboidal to columnar cells. Myoepithelial cells are present between the secretory cells and the basal lamina.
n3. Secretory Product. Apocrine sweat is a viscous, odorless fluid that, once secreted, acquires a distinctive odor as a result ofbacterial degradation. The term apocrine derives from early evidence that the secretory cells of these glands released their apical cytoplasm along with the secretory product. Recent evidence, however, argues against apical shedding. Therefore, although the secretory products ofapocrine and eccnne sweat glands do differ, their mode of secretion-merocrine-is similar.
n1. Distribution. Less numerous than the eccrine type, these glands occur mainly in the axilla, pubic and anal regions, and the areolae of the breasts. 2. Structure. Apocrine sweat glands are also simple coiled tubular glands, but are generally larger than eccrine glands. a. Ducts. These coiled ducts are lined with low cuboidal epithelium and open into hair follicles . b. Secretory portions. Coiled and embedded in the dermis, each has a wide lumen lined by cuboidal to columnar cells. Myoepithelial cells are present between the secretory cells and the basal lamina.
n3. Secretory Product. Apocrine sweat is a viscous, odorless fluid that, once secreted, acquires a distinctive odor as a result ofbacterial degradation. The term apocrine derives from early evidence that the secretory cells of these glands released their apical cytoplasm along with the secretory product. Recent evidence, however, argues against apical shedding. Therefore, although the secretory products ofapocrine and eccnne sweat glands do differ, their mode of secretion-merocrine-is similar.
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