Anatomy and Physiology - Integumentary Flashcards
What is the integumentary system?
The integumentary system refers to the skin and its appendages, including hair, nails, and glands.
Is the hypodermic or subcutaneous tissue a layer?
Stem cells are basically…
immature cells that can become any cell
What is melanin?
The pigment that gives skin its color
Why does burned skin become bacterial infected and inflamed?
your skin no longer has a protection and bacteria gets in… that’s when your innate system comes in and that’s why the skin becomes inflamed
Innate acts fast but…
has no memory
What is HPV?
sexually transmitted infection
What is the difference between shingles and chickenpox?
Shingles and chickenpox are both caused by the same virus, varicella-zoster, but shingles is a reactivation of the virus after a person has had chickenpox, while chickenpox is the initial infection.
The human body can be broken up into what six structural levels?
- Chemical: atoms and molecules
- Cell: the functional units of the body, made up of chemicals
- Tissue: a group of similar cells, four types: epithelial, connective, muscle, nervous
- Organ: two or more types of tissue that together perform a function
- Organ System: a group of organs that considered a unit because of a common set of functions
- Organism: a whole being that can function and live on its own
Functions of the skin are as follows:
- Regulation of body Temperature: changes in blood flow to skin control sweat glands to control body temp
- Protection: provides physical barrier from bacteria, dehydration, UV radiation, etc
- Sensation: contains abundant nerve endings and receptors to detect temp, touch, pressure, pain
- Excretion: removes heat, water, salt, and some organic compounds (via sweat)
- Immunity: contain Langerhans cells which are important for immunity
- Blood Reservoir: contains an extensive network of blood vessels
- Synthesis of Vitamin D: skin contains precursor molecule which is activated by UV rays in sunlight then
converted into vitamin D in liver/kidneys
What are the 2 main layers of the skin?
Epidermis and Dermis
True or False: The epidermis contains blood vessels
FALSE
The epidermis is made of what 4 types of cells?
a. Keratinocytes (90%): produce keratin which is waterproof and protects skin from light/heat,
microbes, and chemicals
b. Melanocytes (8%): produce melanin which is a brown-black pigment that contributes to skin
color and absorbs UV light. Once inside the keratinocytes, the melanin granules cluster to form
a protective veil over the nucleus, on the side toward the skin surface to shield genetic material
from damaging UV light.
c. Langerhans cells: arise from bone marrow and migrate to epidermis to interact with white
blood cells called T cells in immune responses and are easily damaged by UV radiation
d. Merkel cell: located in the stratum basale of hairless skin. Make contact with the ending of a
sensory neuron (nerve cell), called a tactile (merkel) disc and function in the sensation of touch.
what is the deepest layer of the epidermis?
Stratum basale
The epidermis is made of what 5 layers of cells?
a. Stratum basale: deepest layer aka stratum germinativum. Single layer of cuboidal to columnar-
shaped cells which contain melanocytes and stem cells. Stem cells are capable of continued
cell division and multiply, producing keratinocytes which push up towards the surface or
migrate down to the dermis to become sweat glands or hair follicles. Also contain tactile
(Merkel) discs that are sensitive to touch
b. Stratum spinosum: cells covered with prickly spines tightly packed together
c. Stratum granulosum: flattened cells that contain keratohyalin which is a precursor to keratin
(forms barrier that protects deeper layers from injury, microbial invasion; makes skin
waterproof). Nuclei of cells are in various stages of degeneration as they prepare to breakdown.
d. Stratum lucidum: more apparent in thick skin of palms and soles. Clear, flat dead cells that
contain eleidin which is formed from keratohyalin and later transformed into keratin
e. Stratum corneum: outermost superficial layer which consists of flat, dead cells completely filled
with keratin. These cells are continuously shed and replaced by cells from deeper strata.
Serves as an effective barrier against light and heat waves, bacteria and many chemicals
What are stratum spinosum cells?
cells covered with prickly spines tightly packed together
The dermis is a thick middle layer of connective tissue with collagen and elastic fibers and has…
blood vessels
