Integumentary System Flashcards
What is made up of proteins and lipids that surrounds the cell?
Plasma membrane
What are the functions of the plasma membrane?
Defines cell boundaries
Governs interactions with other cells
Controls passage of materials in and around the cell
What is it celled when cells are joined together?
Junction
True or false -
There are four categories of junctions tight, loose, gap, and desmosome.
False - there are three categories of junctions.
Tight, desmosome, and gap
What type of junction uses transmembrane cell-adhesion proteins?
Tight junctions
Where are tight junctions found in the body?
In the skin and digestive track, this makes it so that acid and bacteria can not get places they are not meant to be.
Where are desmosomes found?
In epithelium and cardiac muscle
Explain what a gap junction looks like.
6 transmembrane proteins that are arranged around a pore. Allows ions, nutrients, and small solutes to pass from cell to cell.
True or false -
Secretion is a waste product
False secretion is a useful product
Endocrine and _______ are to two types of classifications of glands.
Exocrine
Explain the difference between exocrine and endocrine glands.
Exocrine glands have contact with epithelial surface through ducts. These surfaces can be internal or external.
Endocrine glands - Secretes directly into the blood, these can be hormones.
What are the two classifications of exocrine glands?
Serous glands - thin and watery fluid
Mucus glands - secretes mucin
Mixed glands - they have the ability to do both
__________ is a type of exocrine secretion that uses a vesicle to travel to the surface and release to the exterior.
Merocrine, used exocytosis. Think tear glands, mammary glands, and pancreous. Think of a pimple
__________ is a type of exocrine secretion that uses cytosol to package and push to the surface.
Aprocrine, they are like little droplets at the surface that bud off
__________ is a type of exocrine secretion that secretes the entire gland.
Holocrine glands rupture at the surface which also includes the plasma membrane. Think of self destruction. Oil glands of the scalp and eye lids.
What does the mucus membrane line?
Passage ways like digestive, respiratory, urinary, and reproductive.
What type of membrane lines the thoracic and abdominopelivc cavities?
Serous membranes that have serous fluid to reduce friction
What are the two primary regions of the integumentary system?
Epidermis
Dermis
(Hypodermis)
What are the six functions of the skin?
Protection - bacteria invasions, physical trauma, UV radiation
Water regulation - Cells that control water in and out
Vitamin D production - Need UV and this is essential for bone production
Sensory information - touch, pain, pressure, and temp
Regulate body temp - Increase and decrease of the temp
Communication - facial expressions
_________ skin has sweat glands and no hair follicles or sebaceous glands.
Thick
What is the outer most layer of the epidermis made of?
Keratinized stratified squamous epithelium. It is the outer region that is thinner. These are dead cells with keratin, they do not have blood vessels.
What are the five cells that make up the epidermis?
Stem cells Keratinocytes Melanocytes Tactile cells Dentritic cells
________ synthesize melanin and are found at the stratum basale. They are used to shield the DNA
Melanocytes
What is the most abundant cell in the epidermis?
Keratinocytes
True or false -
Tactile cells originate in bone marrow and are immune cells.
False Dendritic cells are immune cells that originate in the bone marrow. They are found in the stratum spinosum and stratum granulosm
Where are tactile cells found and what is the function?
Found in the stratum basale and they are touch receptors that are associated with dermal nerve fibers..
True or false -
Thin skin contains 4 strata and thick skin contains 5.
(list them)
True Deepest layer - stratum basale Stratum spinosum Stratum granulosum Stratum lucidum - Not found in thin skin Stratum cornium
What is the stratum basale consist of?
Single layer of stem cells
Keritin fibers
Melanocyts and tactile cells
Free nerve endings for pain and temp
Which layer of the epidermis has several layers of keratinocytes that are held together with desmisomes and tight junctions?
Stratum Spinosum - These have lipid filled, membrane bound organelles. Thick second layer
________ is only found in the thick skin
Stratum lucidum - allows skin to stretch and had better friction control. This is why it is found in thick skin which includes places like palms and feet
During which layer do cells start to lose their nucli and begin to die?
Stratum Granulosum - 3-5 layers of flat keratinocytes, these dying cells will eventually become the final layer
What is the most superficial layer of the epidermis?
Stratum Cornium - Lots of layers of dead and scaly keratinized cells. They will just fall off at all times.
How long does it take for a keratinocyte to go from the stratum basale to the skin surface?
30-50 days. This can vary by age or if the skin is damaged and needs to be healed.
What are the three factors that determine skin color?
Pigment, blood, thickness of the stratum coroneum.
True or false -
Caratene protects against UV
False - melanin does. The amount a person has is determined by genetics, hormones, and exposure to light.
What type of pigment comes from vegetables?
Caratene which is yellow pigment that accumulates in stratum coroneum, adipose cells of the dermis, and subcutaneous tissue.
What type of tissue is the dermis made out of?
Connective tissue
What are the types of fibers inside of the dermis and what are their functions?
Collagen fibers - prevent tearing
Elastic fibers - movement of muscles and joints
What does the edge of the dermis look like that connects with the epidermis? Explain the parts and why this shape is beneficial.
The edge is wavy. The dermal papilla is the upper swing that is attached to the epidermis. The epidermis ridges are the downward waves of the epidermis. This wavy shape reduces slippage, resistance to stress, and gives nutrients to the epidermis.
What are the 6 “regions” that hair grows?
Scalp Beard, pubic, and axillary Eyebrows Hair on the trunk and limbs Guard hairs Eyelashes
The functions of the scalp hair is to _______ ______ and protect against ________ and ________
… is to retain heat and protect against sunburn and skin cancer
________, _________, and ________, hair start growth around maturity.
Beard, pubic and axillary
What type of hair is remnants from evolution, that is also used for sensory inputs?
Hair on the trunk and limbs
What are eyebrows good for?
Facial expressions, reducing glare, and keeping sweat out of eyes.
What type of hairs block particles from entering the nose, auditory canals and eyes?
Guard cells (vibrissae)
________ shield the eyes
Eyelashes
True or false -
Vellus hair is hair that is fine, unpigmented hair that is found on a fetus.
False - Lanugo hair is what is on a fetus before birth
What type of hair do children have?
Vellus hair everywhere except the eyebrows, eyelashes, and hair on the scalp
When does terminal hair replace vellus hair?
Puberty which then forms the axillary and pubic hair along with eyebrows, eyelashes, and scalp.
What makes terminal hair different from other hair types?
It is longer coarser, and more heavily pigmented. This includes male facial hair and hair on limbs and trunk.
What type of biological significant might terminal hair have?
Since it is produced around puberty it might signify that someone is sexually mature. Male hair might also be there to attract females either by looks or holding the scent of pharamones
What are the three zones of the hair and follicle? Explain them.
Bulb - swelling at the base, this is the only loving hair cells and it can be in the dermis or hypodermics.
Root - the rest of the hair that is in the follicle
Shaft - portion above the skins surface
What are the three layers of the hair and follicle?
Explain them.
Medulla - core, loosely arranged cells with air space. This layer is not in thin hair
Cortex - this is the majority of the hair and has several layers of elongated keratinized cells
Cuticle - surface of the hair that have layers that are very thin and have scaly cells that overlap.
A diagonal tube in the epidermis that extends to the dermis and sometimes hypodermis is call the ________.
Hair Follicle
What is the smooth muscle that attaches the follicle to the dermis? What is it responsible for?
Piloereceptor - Contracts in response to stimuli like cold, fear, and touch.
True or false -
The first stage in hair growth is catagen.
False - the first stage is Anagen which is the growth stage. During this stage the follicle grows deeper into the dermis and the hair cells produce keratin and then die.
What happens during the second stage of hair growth?
It is called catagen which is the degeneration stage. mitosis in the hair matrix stops and the follicle shrinks and dies. This makes the base of the hair keratinize.
Explain what telogen is.
It is the last stage of hair growth also called the resting stage, during this stage the chub of the hair falls out.
What are the five types of skin glands?
Merocrine Apocrine Sebaceous Ceruminous Mammary Both Merocrine and Apocrine glands are sweat glands
What is the most abundant type of sweat gland?
Merocrine
Explain merocrine sweat glands
They go directly to the surface through a ducts. They are active with high temps because the sweating will cool the body.
What type of sweat gland open into hair folicules?
Apocrine sweat glands, armpit, anal region, groin, beard.
What do apocrine glands produce and how do they secrete it?
They produce pheromones that contain fatty acids and body odor that is is the apocrine sweat gland and bacteria.
They use merocrine secretion methods
What gland is responsible for the secretion of oil around hair follicles and what type of secretions is used?
Sebaceous glands secrete oil to waterproof/lubricate hair and skin and it kills or weakens the bacterial on skin surfaces.
This is secreted through holocrine secretion which is the breakdown of the entire gland and secretes directly onto the surface of the skin
__________ glands produce earwax.
Ceruminous glands. This is for waterproofing, antibacterial, and blocking of foreign particles
What type of gland is produced during pregnancy and lactation?
Mammary glands and they use apocrine methods of secretion
The _______ layer of the epidermis is absent from most areas of the body.
Stratum lucidum
True or false -
Areolar connective tissue makes up the papillary layer of the dermis.
True
What layer of the epidermis contains the cells that begin the process of keratinization?
Stratum granulosum
