Chapter 6: The Integumentary System

Stratum spinosum

Accounts for most of the epidermis

Sebaceous gland

Acne is an infection of the sebaceous gland. Found everywhere on the body except palms of hands and soles of feet. Gland that secretes and quietly substance

Sebum

And oily secretion that helps to waterproof the body surface

Epidermis

Avascular region. General name of the entire superficial layer of the skin

Some injections and hurt more than others. On the basis of what you have learned about skin structure, can you determine why this is so?

Because hypodermic needles go down further into the skin where there are more nerve cells

Stratum corneum

Dead cells, outermost epidermal layer.

Which layer of the skin or follicles usually found?

Dermis

Melanin

Epidermal pigment

Order of larger skin groups (from outside in)

Epidermis, dermis, hypodermis/subcutaneous

Why is it advantageous to have pain receptors that are sensitive to all vigorous stimuli, whether heat, cold, or pressure?

Example: the back of your hand is less sensitive to heat, so in fires you touch the back of your hand to a door knob and it wont be awful

Which two body areas tested were the least sensitive to touch?

Forearm and back of neck

Keratin

Hard protein of nails and hair

Nail

Has a lunula and cuticle

Stratum granulosum

Layer containing sacks filled with fatty material or keratin subunits, epidermal region exhibiting the most mitoses

Dermis

Major skin area where derivatives (nails and hair) reside, has abundant elastic collogenic fibers. Inner layer of skin

Which cells produce the pigment and hair?

Melanocytes

Eccrine sweat gland

More numerous variety of perspiration gland that produces a secreation containing water, salt, and vitamin C; activated by rise in temperature.

Which two body areas tested were most sensitive to touch?

Palms and fingertips

Hair

Primarily dead/keratinized cells

Arrector pili muscle

Specialized structures that respond to environmental stimuli. Example: causes hair to stand erect and enables goosebumps.

Order of skin structure (from outer layer to inside)

Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale. CLGSB

Hair follicle

Structure that houses the hair. Sheath formed of both epithelial and connective tissues. Tubelike part that contains the root of the hair

How does the skin help to regulate body temperature?

Sweating to cool down, and goosebumps to warm up

Define adaptation of sensory receptors

The decline of the electric responses of a receptor neuron over time in spite of the continued presence of an appropriated stimulus of constant strength. Example: balancing a penny on your arm and forgetting it is there

Stratum basale

The most superficial dermis layer, region where melanocytes are most likely to be found. Cell division and deepest layer of epidermis

What organ system controls the activity of the eccrine sweat glands?

The nervous system

How does the skin on your palm differ from that of the back of your hand?

The palm has a thicker lucidum layer making it thick skin. The back of your hand is a thin skin with a thin lucidum layer.

Pain receptors do not adapt, why is this important?

They always process paying the same way so your body knows it's in danger

Apocrine sweat gland

Type of perspiration producing glands that produce is the secretion containing proteins and fats in addition to water and salts. Becomes active at puberty

What substance is manufactured in the skin (not a secretion) to play a role elsewhere in the body?

Vitamin D

Four protective functions of the skin

Waterproof, protection from UC raise, regulation of body temperature, healing of wounds