1B - Integumentary system Flashcards
Skin is the largest organ in the body, comprising ___ of the total weight of the body.
15%
The thinnest skin is located on _____.
Your eyelids
What is true in the dermis?
- It is deep to the epidermis.
- It is 80% of the thickness of the skin.
- It contains blood vessels and nerves.
- It is composed of a dense irregular connective tissue.
Choose the statement that best describes subcutaneous tissue.
It is loose connective tissue with an abundance of adipose cells.
Your patient has severely low levels of calcium. However, he is ingesting the daily recommended amount, what would explain his condition?
Lack of sunlight and low vitamin D
The skin acts as a barrier to microbes, H2O and various organic and inorganic toxins. Which part of the epidermis is responsible for this characteristic?
Stratified squamous keratinized epithelium
When an injury occurs to the epithelium, how is it repaired?
Mitosis at the basal epithelium
A “sunburn” can occur because of?
Damage to melanocytes
The deepest layer of the skin contains
Connective tissue, nerves, dense irregular connective tissue, and blood vessels
A patient presents a deep laceration to the 2nd phalange of the left hand of which bone is now exposed. Which layer will receive nervous damage?
Epidermis, dermis and subcutaneous tissue
Epidermis
outermost layer of skin composed of stratified squamous keratinized epithelium
The epidermis is ______
avascular; doesnt have blood vessels
Melanocytes
produce dark pigment for skin called melanin
Papillary ridges
finger and toe prints
Vasodilation
When the body is too warm, blood vessels dilate allowing more blood flow and this lowers body temperature
Vasoconstriction
When body is too cold, blood vessels constrict preventing blood flow and conserving body heat
Noiceptors
detecting damage to skin
Langerhans cells or epidermal dendritic cells
Able to destroy invasive pathogens via phagocytosis
5 layers of epidermis
stratum corneum, lucidum, granusolum, spinosum, and basale
Stratum basale
Deepest layer of epidermis and made up of single layer cubodial columnar cells called keratinocytes. Also has melanocytes
Stratum Spinosum
Has several layers of keratinocytes, when basale cells divide daughter cells move up into the spinosum
Keratinocytes of stratum spinosum are
Non-dividing
Other cells associated with the stratum spinosum
Langerhan cells
Langerhan’s cells
immunological cells capable of destroying pathogens that envade the epidermis. Also have been shown to destroy cancer cells
Stratum granusolum
3 to 5 layers of flat cells, Cells of the Stratum Granulosum begin to die. The nucleus and organelles disintegrate and the cells fill with the structural protein keratin (a process
called keratinization).
Straum Lucidum
thin, translucent layer of the epidermis. The stratum lucidum only exists in areas of the body with very thick skin such as the palms of the hands
and soles of the feet.
Stratum corneum
most superficial layer of the epidermis and consists of 20-30 layers of dead keratinized cells called corneocytes
How long does it take for a cell to migrate from the stratum basale to the corneum
2 weeks
What is the dermis composed of?
dense irregular connective tissue containing both connective properties and collagen
What does the dermis include?
blood vessels, sweat and sebacous glands, smooth muscle tissue, hair follicles and sensory nerve endings
How much does the dermis take up of the skin?
80%
Papillary layer
apart of the dermis, lies adjacent to the epidermis and possesses raised projections called the dermal papillae
Reticular Layer
apart of the dermis, possesses the majority of accessory structures associated with the dermal layer of the integument including blood vessels, nerves, sweat glands and hair follicles.
Subcutaneous Tissue aka the Hypodermis
deep in the dermis and contains and it made up of loose connective tissue
Lanugo hair
develops on fetus during the last trimester and is very fine and lacks pigmentation
vellus hair
replaces lanugo hair after birth and is found on most parts of body
Terminal hair
longer pigmented hair found on scalp, eyebrows and eyelashes. At puberty, terminal hair replaces vellus hair in the inguinal and axillary regions.
Anagen phase
can last from 18 months to 7 years and is called the active phase of hair growth
Catagen phase
last from 3-4 weeks and is a period when cellular division has stopped
Telogen phase
last 3-4 months and is a resting period of hair loss
Two types of sweat glands
merocrine and apocrine
merocrine glands
more numerous (3-4 million) high concentrated on the palms and soles of feet and forehead. Dont smell
Apocrine glands
produce a more viscous secretion that contains proteins and lipids that are released into the hair
follicles. Releases body odor, typically found armpit groin and nipples.
Sebaceous glands
oil producing glands usually termed sebum. this is why our hair gets greasy
Folliculitis
localized inflammation of the hair follicle caused by bacterial infection
First degree burns
damage to the epidermis from sun, characterized by edema (swelling), rubor (redness), and dolor (mild to moderate pain).
Second degree burns
damage to the epidermal and dermal layers, present with blistering. Symptoms are more severe and delayed 2-4 weeks
third degree burns
damage to the epidermis, dermis and subcutaneous layers, often caused by toxic chemicals and scolding hot water
