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Bio 230 Lab worksheet- Integumentary System

We will start with the EPIDERMIS. The upper skin region which is keratinized stratified squamous epithelium. Label the layers (strata) of the epidermis below: this is from thick skin. How do you know? Note: Strata = plural, Stratum = singular)

1. Stratum basale 4, Stratum lucidum 2. Stratum spinosum 5. Stratum corneum 3. Stratum granulosum

Besides each layer (strata), Put an: A if that layer has living cells DY if that layer has cells that are dying DE if that layer is only dead cells

Label the cells of the epidermis: a. Keratinocytes a. Melanocyte b. Merkel (aka tactile) cell c. Langerhans cell

Structures in dermis e. Merkel (tactle) disc f. Sensory nerve

Be sure you know the location (strata) each cell located And the function of each cell

Dermal papilla

Dermis (Connective tissue) What is the difference between the epidermal ridge and dermal

papilla? What C.T. in under all epithelial tissue?

Epidermal ridge

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Be sure you can easily ID the 4 strata (layers) of Keratinized stratified squamous ET. Hard to see S. Lucidium so won’t need to ID that layer. Know S. Lucidum only in thick skin.(soles of feet/palms of hand)

ID on both these slides: 1. Stratum basale 3. Stratum granulosum 2. Stratum spinosum 4. Stratum corneum

 Melanin pigment granules (-brown pigment granules) can be seen in cells situated in the lower layer of the epidermis of the skin Image above.

The top region of the skin is called the ______________________,

which is the the epithelium called ____________________________________________________

The skin region just inferior to the E.T. is called the _________________________, and is the area of

connective tissue.

The type of CT just deep to the E.T. is called ___________________________ CT.

The dermal projections marked with X below, are called __________________________________________

and are located the the ____________________________ region of the dermis.

X X X

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Skin Regions 1.Epidermis Type of E.T.=

2. Dermis Subdivided into 2 layers 2a. Top 20% = Type of C.T=

2b. Deeper 80%= Type of C.T=

3. Hypodermis AKA=

Main type of C.T.=

Label Diagram

4. Label the Epidermal Ridge

5. Label The Dermal Papillae

What does “Papilla” mean?

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Name the Strata of the Epidermis

1

2

3

4

5

1.

2.

3.

4.

5.

Name these Structures

6.

7. (the projection)

8.

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Is structure 8 associated with an Endocrine or Exocrine Gland?

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8

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Label: 1. Hair shaft 2. Hair root 3. Hair follicle 4. Hair bulb 5. Hair papilla

Exocrine glands What are Exocrine Glands VS, Endocrine Glands?

6. Sebaceous (oil) Glands

7. Eccrine (sweat) Glands

Apocrine glands are not shown here. Where are APOcrine sweat glands found? When do they start functioning?

Sensory Structures. 8. Meissner’s Corpuscle AKA Tactile corpuscle Found ? Function?

9. Pacinian corpuscle aka Lamellated corpuscles Found? Function?

10. Arrector Pili Muscle

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Examine your classroom model (page 7 of worksheet). Identify the presence (+) or absence (o) of the following structures in each of your three skin sources:

Structures Scalp Axilla Thick skin

Hair

Eccrine sweat gland

Apocrine sweat gland Sebaceous gland

Sebaceous gland

Stratum lucidum

Enlarged dermal papillae

Thick stratum corneum

Looking at your chart and skin model contrast the number of enlarged dermal papillae seen in thick skin Vs. thin skin. What function do you think such differences serve? Remember where you find thick skin !

Looking at your chart and skin model, why is it that acne is never found on the soles of the feet or the palms of your hands?

Your class room model Label your three skin source first (thick skin, thin skin (like scalp) or skin from axilla

Can you locate: 1. hair shaft 2. hair root 3. hair bulb 4. hair papilla 5. Sebaceous oil gland

6. merocrine (eccrine) sweat gland 7. duct of sweat gland 8. Epidermis- know the strata too! 9. dermis 10. papillary region of dermis 11. Reticular region of dermis 12. Hypodermis (aka sub Q)

13. messiner’s (tactile) corpuscles 14. pacinian corpuscle (lamellated corpuscle) Can also be found where? 15. adipose tissue 16. arrector pili muscle 17. apocrine sweat gland

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Skin source: A= B= C=1

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5

6

7

8

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10

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12

13

14

15

16

17

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Stratum Corneum Stratum Granulosum Stratum Spinosum Stratum Basale

Melanocyte

Sweat duct

Eccrine Sweat gland

Merkel cell

Merkel disc

Sensory nerve Sebaceous gland

Hair Follicle (epidermal cells Around the hair root)

Hair Bulb- distal expanded end of hair follicle. Includes the hair matrix

Close up of hair matrix: Hair matrix - keratinocytes) Epidermal cells that create new hair. Hair Is made of keratin! Melanocytes present (give hair it’s color).

Hair Shaft

Hair root

Hair papilla- CT indentation that has blood vessel to “feed” hair matrix

Epidermal Derivatives Study this diagram! What structures come from the keratinocytes of the epidermis?

Are melanocytes and Merkel cells Epidermal derivatives? Why or Why not?

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1.The front and back of the head and neck equal 9% of the body's surface area.

2.The front and back of each arm and hand equal 9% of the body's surface area.

3.The chest equals 9% and the abdomen equals 9% of the body's surface area.

4.The upper back equals 9% and the lower back equals 9% of the body's surface area.

5.The front and back of each leg and foot equal 18% of the body's surface area.

6..The external genitaia/perineum equal 1% of the body's surface area.

Rule of 9 Burn Scale You can quickly estimate the size of a burn by using the "rule of nines." This method divides the body's surface area into percentages.

Example: An adult who has been burned, the percent of the body involved can be calculated as follows: If both legs- front and back (9% x 4= 36%), the ext. genitalia(1%) and the front chest 9% and abdomen 9% were burned, this would involve 55% of the body. 36 + 1 + 9 +9 = 55%

Questions: The integumentary system = the skin + WHAT structures!!!

1. How does the integumentary system help in the regulation of body temperature? What do the terms “vasodilate and vasoconstriction “ mean?

2. Why is the epidermis so vulnerable to “frost bite”?

3. What vitamin is synthesized in the skin (with the help of the sun)? AND why is this Vitamin needed by the body?

4. The epidermis is what type of Epithelium?

5. Name the 5 layers of the epidermis found in the thick skin of the palms and bottoms of your feet. Next to each layer list if the cells are living , dying or DEAD.

6. What layer of the epidermis represents the transition from living to dead epithelial cells? Why do keratinocytes begin to die within this layer?

7. Which of the 5 layers (strata) you listed is not present on your face?

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8. Name the 4 cell types found in the epidermis, where they are found, function of each of these cells and the relative % of each.

9. What is the function of the pigment melanin? How is your body trying to protect you when you lay out to get a sun tan?

10. The papillary layer of the dermis is made up of what primary type of connective tissue? Why is this a good type of C.T. to have under the epidermis?

11. The reticular layer of the dermis is made of of what primary type of connective tissue? Which of these 2 layers (papillary and reticular) gives skin its over all strength and elasticity? Why?

12 . What is the difference between Tactile ( Meissner’s) corpuscles, Tactile (Merkel) cell, and Pacinian (lamellated) corpuscles? Where is each located?

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Cell name Strata found Relative % Basic function

13. What is the difference between eccrine and apocrine sweat glands? Which type is more common?

14. Where would you expect to find more sensory receptors, in your palms (which includes the ventral surface of your fingers or your axillary region?

15. A first degree burn is damage to only the _____________________________________ region of the skin.

A second degree burn goes through the ________________________________ and into the _____________________.

A Third degree burn reaches down past the __________________________, and the _________________________

And into the _____________________________________.

A classic second degree burn has a fluid filled blister. What does this blister represent?.

16. An adult burn victim was brought in to the ER. You are told to estimate the percentage of the body burned. This is your observation of the patients skin once the clothing have been cut away. -back of head burned = ________ %

-upper back burned = _________%

-back of left arm burned = ________%

-back of left leg burned + _________%

-What is your answer regarding the body percentage burned on your patient?

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