1. Dermis Just deep to epidermis Two layers Collagen and elastin
Papillary layer
Reticular layer
Collagen and elastin
Dermal blood supply
Nerve endings
Some muscle tissue
Glands
Hair and nails

2. Papillary Layer Dermis contains TWO layers: _____________
Contains dermal papillae (hence papillary)
Many capillary loops (feed the epidermis)
Base of hair and nails
Nerve endings
Glands

3. Hair Anatomy ______ – shows above skin ______ – below / in the skin
________ - where hair attaches and grows from (clear part when pulled out)
___________ – group of cells that cause growth of hair (they create more cells, causing the others to move upward = growth)

4. More hair…. The hair that you groom daily (shaft) is actually dead
___________________ cells.
Each hair follicle has an associated bundle of smooth muscle, the __________________ muscle. This muscle inserts with one end to the papillary layer of the dermis and with the other end to the hair follicle.
This makes your hair stand up on its end.

5. Hair Color and Texture – fun facts
Hair color is determined by the amount and type of melanin present.
Melanocytes become less active with age. Gray hair is a mixture of pigmented and non-pigmented hairs.
Red hair results from a a modified type of melanin that contains iron.
The shape of the hair shaft determines texture.
Round shaft – straight hair
Oval shaft – wavy hair
Flat shafts – curly or kinky hair
**Perms use chemicals to flatten shafts and makes hair curly.
__________ is the term for hair loss.

6. Nails Plates of cells with hard keratin
Protect distal ends of phalanges
Cells are keratinized in the nail root
Nail growth occurs in the __________
Nail ________ – cells responsible for growth
The cuticle is a fold of stratum __________ on the proximal end of nail

7. Why doesn’t it hurt to cut your cuticles?
Explain….

8. Click here to copy and paste a Picture of the skin and nail here.
Label the following:
Lunula
Cuticle
Nail plate
Nail bed
Lateral nail folds
Nail matrix
Distal edge

9. Glands ____________ glands = “EXIT” the body “Ex”ocrine
Sweat, Oil, Ear wax
All that relate to skin
____________ glands = release contents within the body
hormones

10. _____________ glands They secrete the sebum (seb = oil)
an oily product.
Sebum is usually secreted into a hair follicle.
Sebum is a natural _____________:
prevents excessive evaporation of water from the skin,
keeps the skin soft
contains a bactericidal agent that inhibits the growth of certain bacteria.
Sebaceous glands are scattered all over the surface of the skin except in the __________, soles and the side of the _________.

11. Homeostatic Imbalance:
Pimples = bacteria in oil glands
_____________ – sebaceous gland is blocked and the blockage dries up (oxidized)
_____________ – Sebaceous gland blocked / pus

12. Sweat Glands Eccrine – Found all over the body
secretes directly to the surface of skin via pores
Main function: evaporative cooling
Apocrine –
Activated during puberty
Located in the axillary region, pubic region, and mammary region.
Secrete onto hair follicle (unlike eccrine)
A LOT stronger / potent than eccrine sweat glands

14. Compare and contrast eccrine and apocrine sweat glands

15. Other exocrine glands ______________ glands Related to apocrine glands
Secretes milk
Triggered by hormones
Modified sweat glands
Produce cerumen (_____________)
Helps trap foreign particle from entering

16. Sensory!! (nerve endings)
Meissner’s corpuscles – (tactile)
sensitive to _____________
found in papillary layer
Pacinian corpuscles – (lamellated)
deep __________ and ___________
found in reticular layer

17. More Fun Facts!! House dust is mainly skin flakes!
If you laid out all your skin on a flat surface, it would have an area of about 2 square meters.
Skin weighs about 2.5 kilograms - the largest organ in the body.
What hurts if you pull it, but doesn't hurt if you cut it? Your hair, of course!
Skin is elastic - it springs back into shape when stretched. Some medicines (estrogen, nicotine) can pass through the skin, but others cannot (insulin). Why is that? Because only fat-soluble substances can enter the skin, not water-soluble ones.
Your hair stands on end and you develop 'goose bumps' because there are tiny muscles attached to the hair follicles and they contract when you are frightened or cold.