Integumentary System

The skin and membranes

Body Membranes

• Epithelial MembranesA. CutaneousB. MucousC. Serous

Body Membranes

• Connective A. Synovial

Functions of the Skin

1. Protect

2. Excrete wastes

3. Regulate Body temp.

4. Make Vit. D and protect against UV

Parts of the Skin

• EpidermisA. Corneum –top

layer, dead.

B. Lucindum – keratinonly in feet and hands

C. Granulosum – Middle layer

D. Spinosum – keratinE. Basale – bottom

Cell division

Proteins and Pigments of Epidermis

• Collagen – protein fibers, strengthen skin• Keratin – waterproofs skin• Melanin – pigment, blocking UV rays• Carotene - pigment

Parts of the Skin

• DermisA. Papillary layer• Provide nutrients and • Sensation for epidermis

B. Reticular layer• Glands• Pressure receptors• Phagocytes

Receptors of the Dermis

A. Free Nerve endings - pain

B. Krause’s end bulbs – temp.

C. Meissner’s Corpuscles - touch

D. Pacinian Corpuscles - pressure