Integumentary System Flashcards
What the functions of the integument?
It is one of the main homeostatic organs. It provides a barrier between your high ordered regulated internal environment and the outside.
It acts as a physical barrier and protects against infection, through secretions mAintibg the normal flora.
It is a major sensory organ. Provides a source of pain, light and heavy pressures and temperatures sensation.
It is impervious (doesn’t allow to go through) to most chemicals and is moderately to water, although certain other substances can pass through
It protects against damaging radiation like UV
Interstitial fluid
A thin watery fluid that produces by blood, a filtrate, living cells have to have to be bathed in the fluid.
Where is most of your sensitivity located?
Mostly in the skin
What is the surface skin? And what kind of cells is it made up of?
Epidermis and it’s made up of squamous epithelial cells
Which later is the thickest layer of your Integumentary? And what does the it contain?
The Dermis is the thickest part and it contains blood vessels, sense, glands, hair roots
Which tissue layer is not considered apart of the integument?
Hypodermis
What is the epidermis function and what type of cells is made up of?
The epidermis is the most superficial layer of the integument. It’s made up of stratified squamous epithelium. It’s constantly being regenerated from the basal layer.
The top layer consist of dead keratinized cells, which protect from infection and desiccation.
It also produces a pigment called melanocytes to protect against UV rays
Describe the layers of the epidermis
Stratum básale (basal layer) populated by stem cells for keratin/melanin . Constantly undergoing mitosis to replace upper most layers lops. Tight bond to basement membrane and it is attached to the dermis.
Starts spinosum (spinous layer) cells maintain their attachment to each other through desosomes. Appear spikey
Stratum granulosum- cells rapidly keratinized and undergoing programmed cell death.
Stratum Lucidum/corneum- dead keratinized cells forming the outermost
Cell types of integument
Keratinocytes - most commons cells. Produce a waxy protein keratin, which remind Inter the cell and eventually kills it. Protects skin and tissue
Melanocytes - can be atomized to produce brown pigment, melanin by UV light. Humans very in the amount of melanin produced by the skin, but not so much in the # of melanocytes. Absorbs UV and determina skin color
Merkel’s (tactile) cells- most superficial of the sensory receptors cells (stratum básale). Sensitive to light tough. A lot in finger tips and lips. Detect touch stimuli and transmits signals and sensory nerves.
langerhans cells - early waning system of immune system located up the stratum gránulos.assist in immune responses by identifying harmful microbes. Partícipes immunity
Fibrous cells - produce. Fibrous protein called collagen
Describe the structure and function of the dermis
The thickest of layers made up of dense irregular connective tissue, rich in collagen, fibers and populated by fibroblast.
Unlike avascular epidermis the dermis is rich in blood vessels, nerve endings, exocrine glands and the roots of hair aNd nails
These are regios of elastic fibers. Provinces elasticity to the skin.
The dermis is separated into superficial layers. Thinkcker deeper rectiulR layer
Dermis layers
Papillary layer - accounts for 20% of the total thickness as of the dermis. It is deeply folded into papilas thag contain Messiners corpuscles for tactile sense - supples the básale
RecticulR layer - composed of ittegUkr connective tissue with large bundles of randomly organized collagen. This is also the layer that contains elastin
Hypodermis
Held loosely o to the underlying muscle and bone of the hypodermis, a loose connective areolar tissue
PArts of the hypodermis consists of modified loose connective tissue called adipose tissue. Women have more than men. Aidimpose is a lipid storage tissue - which can thicken or thin depending on the calories intake
Adipose is a also a good insultantes tissue and protects the body against hypothermia
List the layers of the epidermis
Stratum Corneum - the superficial layer of the cells - is composed of dead keratinocytes.
Stratum lucidum - is a single layer of translucen, dead keratinizcttes found only in the skin of the palms and soles of the feet.
Stratum granulosum - 3rd layer of keratinocytes. The superficial keratinocytes are dead but the deeper cells are alive. This layer is names for the cells cytoplasmic granules, which contain keratin and a lipid based substance. The lipid based substance is found in lamellar granules and help to keep the skin water resistant.
Stratum spinosum - the first actively metabolizing cells are encounters in the 4th layer. The pigment melanin is found in this layer which provides protective from UV light and also decreases production of vitamins d (to prevent body from over producing it)
Stratum Basel - the deepest layer - consist of single row of actively divining keratinocytes. Here we also find melanocytes, which profuse melanin , and sensory receptors cells called Merkel cells… which function in light touch and texture discrimination.
Which epidermis layer contains melanin ?
Stratum spinosum
Why does the epidermis have so many dead cells?
The epidermis is composed of epithelial tissue and epithelial tissue is avascular (has no blood supply)
All epithelial tissue require oxygen and nutrients to diffuse to them from the report tissues. In this case, the dapper tissue is the dermis so the dermis. Only the cells of the stratum granulosum, spinosum, Basel are close enough to the blood supply in the dermis - to get oxygen and nuttiest for survival. So as the cells migrate further away from the blood supply they die.
