Integumentary System - Words Flashcards
integumentary system
an extremely large, flat, flexible body system that covers the entire surface of the body
What does the integumentary system include?
- skin (epidermis and dermis)
- sebaceous glands
- sweat glands
- hair
- nails
What is the purpose of the integumentary system?
- protecting the body
- sense of touch
integument
skin, hair, and nails
epithelium
epithelial tissue
basic type of tissue that covers the external surface of the body, but also includes the mucous membranes that line the walls of internal cavities that connect to the outside of the body
What are the two layers of the skin?
epidermis & dermis
What is the dermis categorized as?
connective tissue
epidermis
thin, outermost layer of the skin
keratin
a hard, fibrous protein
What does the most superficial part of the epidermis contain?
dead cells that have no nuclei and are filled with keratin
exfoliation
the process of constantly shedding or sloughing off the outer protective layer of dead cells
basal layer
layer of the epidermis composed of living cells that are constantly dividing and being forced to the surface
Are there blood vessels in the epidermis?
no
melanocytes
pigment cells that produce melanin
melanin
a dark brown or black pigment
dermis
thicker layer beneath the epidermis
collagen fibers
firm, white protein connective tissue fibers throughout the dermis
elastin fibers
elastic, yellow protein fibers in the dermis
What does the dermis contain?
- collagen and elastin fibers
- arteries
- veins
- neurons
- hair follicles
- sebaceous glands
- sweat glands
dermatome
a specific area on the skin that sends sensory information to the spinal cord
What is a “C” dermatome?
dermatome with a spinal nerve entering the spinal cord at the level of the neck
What is a “T” dermatome?
dermatome with a spinal nerve entering the spinal cord at the level of the thorax
What is an “L” dermatome?
dermatome with a spinal nerve entering the spinal cord at the level of the lower back
What is an “S” dermatome?
dermatome with a spinal nerve entering the spinal cord at the level of the sacrum (last bone in the spinal column)
How does the face send sensory information?
through the cranial nerves to the brain
sebaceous glands
oil glands
a type of exocrine gland that secretes sebum through a duct that goes into a hair follicle
exocrine gland
gland that secretes its products through ducts opening onto an epithelium instead of into the bloodstream
sebum
consists of oil that coats and protects the hair shaft to keep it from becoming brittle
sweat glands
exocrine glands in the dermis that secrete sweat onto the surface fo the skin through a pore
What does sweat contain?
- water
- sodium
- small amounts of body wastes
> ammonia
> creatinine
> urea
What actually causes the odor associated with sweat?
the waste products of bacteria on the surface of the skin that digest sebum and sweat
perspiration
the process of sweating and the sweat itself
sudoriferous glands
sweat glands
follicle
small sac in the dermis in which a hair forms
What does hair contain?
- melanocytes (to give color to the hair)
- keratin (to make the hair shaft strong)
piloerection
when the skin is cold, a tiny erector muscle at the base of the hair follicle contracts and causes the hair to stand up
What does piloerection do in furry animals?
creates an insulating layer and traps heat near the skin
What do the nails do?
cover and protect the distal ends of the fingers and toes because these areas are easily traumatized
nail plate
the tough, opaque outer layer of the nails
- composed of dead cells containing keratin
- rests on the nail bed
nail bed
quick
layer of living tissue that contains nerve cells and blood vessels
What gives the nail plate its color?
blood vessels in the nail bed
cuticle
an edge of dead cells arising from the skin along the proximal end of the nail
nail root
- located beneath the skin of the finger
- produces keratin-containing cells that form the nail plate
lunula
visible, white part of the nail root
- the whitish half-moon
subcutaneous tissue
loose, connective tissue
- not considered to be part of the integumentary system
- composed of adipose tissue
- could be from very thin to several inches thick
adipose tissue
fat that contains lipocytes
lipocytes
cells in the subcutaneous tissue that store fat as an energy reserve
What are the functions of the subcutaneous tissue?
- provides a layer of insulation to conserve internal body heat
- acts as a cushion to protect the bones and internal organs
- stores energy
allergy
allergic reaction
a hypersensitivity response to certain types of antigens known as allergens
allergens
certain types of antigens - cells from plant and animal sources > food > pollens > molds > animal dander - dust - chemicals - drugs
histamine
a chemical involved in all allergic reactions
What cells release histamine in an allergic reaction?
- basophils in the blood
- mast cells in the connective tissue
local reaction
allergic reaction occurring when an allergen touches the skin or mucous membranes of a hypersensitive individual
- redness (erythema)
- swelling (edema)
- irritation
- itching (pruritus)
systemic reaction
allergic reaction occurring when allergens are inhaled by, ingested by, or injected into a hypersensitive person, causing symptoms in several body systems, and histamine:
- constricts the bronchioles
- dialates the blood vessels throughout the body
- causes hives on the skin
anaphylaxis
anaphylactic shock
severe systemic allergic reaction that can be life threatening
symptoms include:
- respiratory distress
- hypotension
- shock
What are some possible causes of anaphylaxis?
- eating peanuts
- being stung by a bee
- taking a drug that has caused a past allergic reaction
- being exposed to latex gloves
superficial wounds
open wounds that damage only the epidermis
partial thickness wounds
open wounds that damage both the epidermis and the dermis
full-thickness wounds
open wounds that penetrate into or beyond the subcutaneous tissue
acne
a condition of clogged oil pores
What is the purpose of the cuticle?
to prevent microorganisms from entering the nail root
What are the layers of the epidermis?
- the dead, outer layer consisting of keratin-containing cells
- the basal layer
