Integumentary System
The body system made up of the hair, nails, & skin.
Epidermis
The outermost layer of the skin.
Epithelial Cells
The living cells in the epidermal layer of the skin.
Dermis
The innermost layer of the skin; where nerves, glands, blood vessels and hair follicles are located.
Subcutaneous Layer
Another name for the hypodermis.
Hypodermis
The layer below the skin that contains adipose and connective tissue, & helps keep the body warm.
Adipose Tissue
Fat tissue.
Hair Follicle
A small cavity in the skin containing living cells from which hair grows.
Arrector Pili
Tiny muscles in the skin that cause hair to stand up and create "goose bumps" to help keep a person warm.
Functions of the Skin
Regulate body temperature; Prevent infection; Protection from harmful sun rays; Making Vitamin D; Preventing dehydration; Sensing the environment around it.
Keratin
A tough protein found in your skin, hair, and nails.
Nail Fold
The skin on the side of nail that holds it in place.
Nail Cuticle
Base of nail that keeps debris out of matrix.
Lunula
The pale half moon shaped area of the nail, which is part of the nail matrix.
Nail Bed
The area underneath the nail that appears pink due to blood vessels located there.
Melanin
One of the two pigments that affect skin color & which comes in two forms (red-orange and dark brown).
Carotene
One of the two pigments that affect skin color & which gives the skin a slightly yellow tone.
Melanocytes
Specialized cells along top of dermis that produce melanin.
Ultraviolet Light
Very high-energy light produced by the sun that can cause skin cancer.
Albino
An individual unable to produce melanin.
Elastin
A protein found in the connective tissue of the skin which makes it elastic.
Sebaceous Glands
Oil glands in the skin that secrete sebum.
Sebum
An oily substance that coats the skin and hair, keeping them smooth & supple and killing many kinds of germs.
Sweat Glands
Glands in the skin that produce sweat and help cool the body.
Matrix
The living, growing base of the hair follicle or nail.
Shaft
The part of the hair made up of dead cells that sticks out of the surface of the skin.
Cuticle
The clear outside layer of the hair shaft.
Cortex
The layer of the hair shaft that contains the color.
Medulla
The innermost layer of the hair, made of loosely connected cells, which is not always present.
Hair Follicle Shape
What determines if a person has straight, wavy, or curly hair.
Qualities of the Skin
Stretchy; Water-resistant; Flexible; Self-repairing.
Cleavage Lines
Patterns of tension in your skin that go deep into your dermis; responsible for unique finger prints
Free Nerve Endings
Dendrites, located close to the surface in the epidermis, that sense changes in temperature, pain, itch, or skin movement.
Meissner's Corpuscles
Tiny "ball" sensors that give you the ability to tell the distance between two objects that are close together.
Hair Follicle Receptors
Sensory neurons that are wrapped around each hair follicle.
Pacinian Corpuscles
Sensors in the mid dermis that can feel vibration and pressure.
Symptoms of Heat Exhaustion
Heavy Sweating; Pale Skin; Muscle Cramps; Tiredness; Weakness; Dizziness; Headaches; Nausea or Vomiting; Fainting.