Integumentary System

Integumentary system

Skin and underlying fat

What are the layers of the skin

Epidermis, Dermis, Subcutaneous

What are the functions of the intrgumentary system

Protection,

blood reservoir,

cutaneous sensation,

excretion/secretion & absorption,

vitamin D synthesis.

What are the layers of the epidermis

Corneum

Lucidum

Granulosum

Spinosum

Basale

Which layer is only present in Thick Skin

lucidum

Stratum basale

Deepest layer

Single later of cells/skin

Creation of new cells happen here

Stratum spinosum

Numerous layers of keratinocytes

Some retain the ability to divide

Stratum granulosum

Transition layer

Some cells alive and dead

Stratum Lucidum

3-5 layer of thick dead keratinocytes

Thick skin only

Stratum Corneum

Variably thick layers of deat flatted Corneocytes (keratinocytes)

Epidermis

Keratinized thick flat epithelial tissue

Keratinocytes

Produces keratin & lamellar granules

Melanocytes

Produce melanin

Langerhans cells (intraepidermal macrophage)

Immune reponse

Merkel (Tactile Epithelial) cells

Touch receptor

Dermis

thick, middle layer of skin located directly beneath the epidermis

Cells of the Epidermis

• Keratinocytes

• Melanocytes

• Langerhans cells:

• Merkel cells (Tactile cells):

Cells of the Dermis

Fibroblasts

Macrophages

Adipocytes

Lines of Cleavage/ Tension lines

Created by elastic fibers

Clinically : Wounds/incisions that follow these lines generally heal better, while wounds across them tend to experience greater tension.

Hypodermis

Deep to Dermis

Major tissue is fat in this layer

What is a gland?

Epithelial tissue specialized to secrete substances

What are the 2 major types of glands

Endocrine and exocrine glands.

What do sebaceous glands produce?

Sebum

What are sebaceous glands associated with? When do sebaceous glands become active?

Hair follicles.

They become active around puberty.

What are sudoriferous glands?
What are the two types of sudoriferous glands?

Sweat glands

Eccrine and apocrine glands.

What are eccrine glands important for?

Thermoregulation

Where are apocrine glands primarily associated with?

armpit, beard region, and external genital region.

What are apocrine glands associated with?

Odor