Transcript The Integumentary System

The Integumentary
System
Stephanie Childs
Jean-Philippe Dion
Valancy Miranda
Genevieve Perreault-Murphy
Anatomy and Physiology of the Skin
Epidermis
Dermis
Hypodermis/Subcutaneous Layer
The Skin
Epidermis
Protects, senses, insulates, and regulates temperature
• Stratum Corneum
Consists of dead cells
• Stratum Granulosum
Stratified squamous
• Stratum Spinosum
Langerhans’ cells function in defense
• Stratum Basale
Columnar cells
Merkel’s cells function in sensation
Melanocytes produce melanin (skin shade)
Epidermis
Dermis
Provides nutrients, removes wastes, protects, senses
• Collagen
Retain water
Connected by elastin fibres
• Hair Follicles
Insulate, protect and regulate temperature
Held by erector pili muscles
Oil and scent glands are located near the follicle
• Sweat Glands
Produce sweat
• Blood Vessels
Bring nutrients and O2 to skin, and remove waste
• Nerves
Transmit sensory messages to brain
Dermis
Hypodermis/Subcutaneous Layer
• Made mostly of fat and connective
tissue
• Insulates
• Cushions
• Connects skin tissue to surrounding tissues
The Human Fingernail
Cross-section of Human Hair
How the System Contributes to the
Overall Well-Being of the Organism
Protection
Homeostasis
Sensory Functions
Secretion
Protection:
Provides a barrier against potentially
harmful agents
• Nails protect the tips of fingers and
toes
• The skin serves as a barrier
• Melanocytes protect the skin by
providing its colour
Nail Bed
Homeostasis:
Preserving the Internal & External
Environments
• The skin and hair provide insulation
• The skin cells synthesize melanin and
carotenes, which give the skin its colour
• The skin assists in the synthesis of
vitamins
• The skin serves as a selectively permeable
membrane, allowing the passage of certain
substances to the bloodstream
Sensory Functions:
Provides information and responds to
various stimuli
• The skin houses many types of sensory
receptors called cutaneous receptors
• Include phasic receptors (hair follicle
receptors and Meissner’s corpuscles)
and tonic receptors (Ruffini endings
and touch dome endings)
• Pacinian corpuscles are sensitive to
pressure
Sensory Receptors in the Skin
Secretion:
Secretes Chemicals and Sweat
• The skin protects the body by secreting
chemicals on its surface
• The skin’s pH is acidic (3 to 5), which inhibits
the growth of many microorganisms, due to
oil and sweat glands
• Sweat secretions also include the enzyme
lysozyme, which digests bacterial cell walls
Sweat Gland
(Secretory Portion)
Diseases Affecting
the Integumentary System
Skin Cancer
Alopecia Areata
Acne
Eczema
Psoriasis
Rosacea
Skin Cancer
• Melanoma
It affects the melanocytes (cells that give skin its
colour)
Signs can be moles that appear and grow in size
• Basal Cell Carcinoma
Affects the basal cells located in the epidermis
• Squamous Cell Carcinoma
A type of skin cancer arising in squamous cells
(flat cells on surface of skin)
Melanoma
Basal Cell Carcinoma
Squamous Cell Carcinoma
Acne
• Acne refers to plugged pores, pimples and
even deeper lumps that can occur on the
face, neck, chest, back and shoulders
• Types of acne include Comedo, Papule, Macule
and Cyst
• Acne can be treated by:
Reducing sebum production in the skin
Reducing P. acnes (acne bacteria)
Normalizing the shedding of skin cells
Acne
Psoriasis
• A chronic, genetic, non-contagious disorder
that can affect the skin, nails or scalp
• Types of Psoriasis include:
Pustular Psoriasis
Plaque Psoriasis
Erythrodermic Psoriasis
Gutate Psoriasis
Psoriasis
Alopecia Areata
Inflammatory, hair loss disease that
can affect men, women and children
Possibly an autoimmune disease where
an individual’s own immune system
prevents hair follicles from producing
hair fibres
There are several other factors that
may affect the onset of alopecia
Alopecia Areata
Eczema
It seems to be linked to an abnormal response of
the body’s immune system. The inflammatory skin
response to irritating substances is overactive.
Usually characterized by dry, red and itchy
patches on the skin
New drugs known as Topical immunomodulators
can be used to modulate the responses of the
immune system to different irritating substances
Eczema
Rosacea
A chronic disease that causes redness and
swelling, primarily of the face
Some scientists believe that heredity is what
causes the blood vessels in the face to dilate
Another theory is that a mite known as
Demodex folliculorum lives in the hair
follicles and could be the cause of rosacea
Rosacea
Comparative Anatomy of the
Integumentary System
All Vertebrates
Mammals
Other Vertebrates
Arthropods
All Vertebrates Share…
• Two basic layers, the dermis and epidermis
• Structures such as hair and feather follicles
found in the dermis
Mammals
• Some kind of hair covering their bodies
• Some non-human structures present
in other mammals
Horns
Antlers
Comparison of Horn and Antler
Claws
Hoofs
Nails
Comparison of Claws, Hoofs and Nails
Amphibian
Bony Fish
Birds
Comparison of Other Vertebrates
• Amphibians
Skin is smooth, moist, loosely attached to
underlying muscles
No scales, hair or sweat glands – instead mucous
glands in the upper dermis
• Bony Fish
Recovered by a coat of mucous to prevent infections
Layers which compose scales
• Birds (Class Aves)
Feather types: flight, down, contour, filoplumes
Scales similar to reptiles on legs and feet
Arthropods
• Exoskeleton made primarily of chitin
• Most important layer
of the exoskeleton is the
cuticle
• Crustacean organisms
tend to have large
deposits of calcium
carbonate, whereas
many terrestrial
organisms lack a
waterproof lipid layer
The Arthropod Integument
Works Cited
“Comparative Anatomy - Topic 6: The Integument” from the Auburn University website.
http://www.auburn.edu/academic/classes/zy/0301/Topic6/Topic6.html Last updated
Feb. 12 2002, Accessed April 14 2004.
Johnson, Laubengayer Cole and DeLanney. Biology, Third edition. Holt Rinehart and Winston.
New York: 1966. p. 359
Winchester, A.M. Biology and its Relation to Mankind, Fourth Edition. Van Nostrand Reinhold
company. New York: 1969. p. 449-452.
Farb, Peter. “The Insects” from the Life Nature Library. Time inc. New York: 1962.
p.34-35.
Hutchison, Rob. “How the Arthropod Skeleton has been exploited in the Colonization of the
Land” from Veterinary Entomology. http://www.roberth.u-net.com/ectoskel.htm. Last
Update: July 11 1998. Accessed April 18, 2004.
Raven, Peter H. & Johnson, George B. Biology, Sixth Edition. McGraw Hill Publishing Company.
New York: 2002.
http://www.udel.edu/Biology/Wags/histopage/colorpage/cin/cin.htm
http://sln.fi.edu/biosci/systems/integumentary.html
http://shs.westport.k12.ct.us/mjvl/anatomy/mandalaweb/integumentary.htm
http://www.geocities.com/medinotes/his_integumentary_system.htm
http://www.sirinet.net/~jgjohnso/skin.html
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookINTEGUSYS.html
http://www.cancerindex.org
http://www.keratin.com
http://www.skincarephysicians.com
http://www.scro.police.uk/images/sfs/epidermis.gif
http://www.occunomix.com/images/dermis.gif
http:www.sirinet.net/~jgjohnso/ skin.html
http://fig.cox.miami.edu/~cmallery/150/neuro/49x1.jpg
http://academic.wsc.edu/faculty/jatodd1/ap1/nail.jpg
http://www.sirinet.net/~jgjohnso/hairfoliclenew.jpg