Introduction of skin,layers of skin and ANS & its division

1. Nootan Physiotherapy College,
Visnagar.
Prepared By:
Dr. Nidhi Vedawala

2. Integument System
 Integument System
 Organs
 Skin
 Hair
 Nails
 Glands
2

3. Integument System
 Functions
 Protection
 Abrasion
 Infection
 UV light
 Dehydration
 Thermal Regulation
 Insulation (fat keeps you warm)
 Cooling (sweating cools you down)
 Sensory Reception
 Vitamin D Production
 Communication (raised eyebrows)
NOTE
Vitamin D is made in the dermis of the skin, after exposure to sunlight. It’s function is to allow
calcium to be absorbed from the foods you eat so your blood calcium levels are normal. 3

4. The Skin
Skin – our largest organ
 Accounts for 7% of body weight…it weighs twice as
much as your brain!
 Divided into three distinct layers
 Epidermis (‘epi” means above something)
 Dermis
 Hypodermis (“hypo” means deep to something)
 A hypodermic needle means a long hollow needle that reaches
all the way from the epidermis to the hypodermis.
Remember, the term “SKIN” refers to all three
layers: epidermis, dermis, and hypodermis. 4

6. EPIDERMIS
 Primarily made up of keratinized stratified squamous
epithelium
 The EPIDERMIS is the layer that gives strength to the skin.
 Varies in thickness from a few cells (eyelids) to dozens of
cells thick (palms and soles of feet)
 It does not have any vascularization (blood supply), so it
relies on absorbing oxygen and nutrients from the blood
vessels in the dermis deep to it.
 The nails are made in the epidermis.
6

7. Layers of the Epidermis
 Stratum corneum (most superficial layer of epidermis)
 Stratum lucidum (only in thick skin)
 Stratum granulosum
 Stratum spinosum
 Stratum basale (the deepest layer of epidermis)
7

8. How to remember the layers of the epidermis
 The epidermis has five layers. From deep to superficial, they are the
stratum basale, stratum spinosum, stratum granulosum, stratum lucidum,
and stratum corneum.
 To remember which one is the deepest layer, visualize your basement. That
is the stratum basale.
 To get from your basement (deepest layer) to the roof (superficial layer),
walk up your basement stairs...be careful! They are covered with cactus
spines (stratum spinosum).
 That leads you to the kitchen, where someone has spilled sugar all over the
floor (stratum granulosum).
 Then you go upstairs and stop to put on suntan lotion before you go to the
roof. The stratum lucidum is like a layer of suntan lotion; it protects from
UV rays, but is only present on the palms and soles, so that's where you
picture yourself applying the lotion.
 Now you are ready to go to the roof and enjoy a nice popcorn (stratum
corneum). 8

9. Epidermal Cells and Layers

10. The ANS is part of the efferent portion of the peripheral
nervous system

11. Functions
 Regulation of heartbeat
 Smooth muscle contraction
 Secretions of glands
 It is controlled by the hypothalamus with input from the
cerebral cortex and limbic system

12. Comparing the Somatic and Autonomic
Nervous System

13. Somatic Nervous System
 Receptors (sensory neurons) are sensitive to external
environment and transmit signals to the CNS
 Causes stimulation of reflexes or conscious sensation
 Information from efferent fibers sent to skeletal muscle
 Cell bodies located in CNS; only one motor neuron involved

14. Autonomic Nervous System
 Internal environment
monitored by interoceptors
 Stimulation of ANS rarely
results in conscious
sensations
 Visceral Effectors: smooth,
cardiac muscle and glands
 Pathway involves TWO
motor neurons in sequence
 Preganglionic neuron cell
body is in CNS;
Postganglionic cell body is
outside CNS
 Axon fibers of 2nd neuron
not myelinated and release
ACh or NE

15. Sympathetic Division - Flight or Fight
Parasympathetic Division - Rest or Response

16. Differ in location of preganglionic cell body
 Sympathetic Division (Thoracolumbar) - cell bodies located in
lateral gray horns of thoracic & lumbar regions of spinal cord
 Parasympathetic Division (Craniosacral) - cell bodies found in
cranial & sacral regions of the cord

18. Sympathetic Responses
 Pupils and bronchioles dilate
 Heart and respiration rate increases
 Dilation of blood vessels to skeletal muscles
 Constriction of vessels to nonessential organs- BLOOD
PRESSURE ZOOMS UP
 Secretion and motility to digestive structures inhibited

19. Parasympathetic Responses
 Constriction of pupils and bronchioles
 Decreases respiration rate; slows down the heart
 Increases blood flow to GI tract
 Decreases blood flow to skeletal muscle
 Kidneys begin to function - urination
 Erection on both male and female