3 main layers: _____________ Thin layer of _________ ___________ epithelium

1
BI 201 Human Anatomy Physiology
What are the main layers of the Integ. System?
3 main layers_____________Thin layer of
_________ ___________ epithelium
___________Thicker, tough layer of _______
__________ connective tissue and other components
2
BI 201 Human Anatomy Physiology
What are the epithelial details?

• Most ___________ layer
• Comprised of stratified squamous epithelium
• Most cells are _____________ (become
  filled with keratin)
• Some cells are ___________ (give skin its
  pigmentation) ___________ (immune cells)

• Outermost layer sloughs off takes ___ - ____
  days to replace

3
BI 201 Human Anatomy Physiology
What are mites and motes?
Most of the dust floating in sunbeams, covering
the tops of bookshelves etc. is desquamated
keratinocytes (i.e. _______ _____ ____) ______
______ (Dermatophagoides) eat these cells. House
dust allergies are generally Dust mite ______
_______________
4
BI 201 Human Anatomy Physiology
Is the epidermis homogenous deep to superficial?
5 layers (strata) _____
Deepest layer, mitosis, pushes new cells upwards
During histo-prep cells pull apart still
mitosis
________
__________
Keratohyalin granules, lamellar bodies release
lipids
The cell dies, organelles deteriorate leaving
keratin
________
Thick layer of keratinized (dead) cells that
sloughs off
________
5
BI 201 Human Anatomy Physiology
Take 5!!!
Some drugs are administered by applying the drug
to the skin (ex., a nicotine patch). The drug
diffuses through the epidermis to the blood
vessels in the dermis. What kind of substances
can pass easily through the skin by diffusion?
What kind have difficulty?
Discuss with your neighbor and predict an answer.
6
BI 201 Human Anatomy Physiology
Why are some people so thick skinned?
Thick and Thin skin refers to ________ ______
not dermis or skin
Thick skin
7
BI 201 Human Anatomy Physiology
Why are some people so thick skinned?
_____ ___ Not all 5 layers present, but hair
is!
8
BI 201 Human Anatomy Physiology
What are the Dermis Details?

• Contains all the goodies
• 2 layers _________ layer _________ layer

Dermis is primarily what type of tissue? Consists
of _________, _________ ____ and ___________ and
_____
What types of fibers? __________________________
_
9
BI 201 Human Anatomy Physiology
What are the Dermis Details?
2 layers Reticular layer Papillary layer
What is the function of the papillae?
10
BI 201 Human Anatomy Physiology
How, what, where and why do we have
fingerprints?
Epidermis of some skin follows contours of
__________ _________ ______.
Is this in thin or thick skin?
11
BI 201 Human Anatomy Physiology
Are all incisions created equally?
___________ (cleavage) _____
The fibers in the dermis are not arranged
___________ at ________. Greater strength in
lines due to orientation of ____________
________.
Surgeons make incisions parallel to tension lines
when possible
12
BI 201 Human Anatomy Physiology
Is the skin equally strong in all directions?
________ (stretch marks) As the skin is stretched
the dermis ruptures and forms linear scars
(____). Striae gravidarum lineae albicantes
Lets predict the orientation of tension lines
based on the direction of striae!
13
BI 201 Human Anatomy Physiology
Is the skin equally strong in all directions?
14
BI 201 Human Anatomy Physiology
What are the Hypodermis Details?

• _________, ______ ____ (____ of body fat) and
  macrophages

• Primarily ______ _________ tissue
• Also called _____________ or ___________ tissue