Lecture 1 - Integumentary system

Question 1

List and describe the components of the integumentary system

Answer 1

1. skin
2. Epidermal derivatives
   
   1. hair follicles
   2. hair
   3. sweat glands
   4. oil glands

Question 2

List, Identify, and describe the two layers (and sub layers) that comprise thick and thin skin

Answer 2

1. Epidermis
   
   1. Stratum basale
   2. Stratum Spinosum
   3. Stratum granulosum
   4. stratum lucidum
   5. Stratum corneum
2. Dermis
   
   1. Papillary layer
   2. reticular layer

Question 3

What are the embryological precursors for the epidermis? Dermis?

Answer 3

The epidermis is derived from the ectoderm, and the dermis is derived from the mesoderm

Question 4

Where is thick skin located? Thin skin?

Answer 4

Thick skin is palms of hands and soles of feet. Thin skin is everywhere else

Question 5

What are the cells of the epidermis?

Answer 5

• Keratinocytes - formation of water barrier (85%)
• Melanocytes - pigment (5%)
• langerhans cells - antigen producing (2-5%)
• merkels cells - mechano receptor (6-10%)

Question 6

What do keratinocytes do?

Answer 6

Produce keratin (intermediate filaments) and also lamellar bodies which contribute to the epidermal water barrier.

Question 7

How do you differentiate the stratum basale?

Answer 7

Simple cuboidal/ low columnar at the base of the epidermis

Question 8

How do you differentiate Stratum spinosum?

Answer 8

It is the largest layer immediately following basale but without the dark granules of stratum granulosum

Question 9

What layer are melanocytes found?

Answer 9

Stratum basale (with extensions into spinosum)

Question 10

What layer are langerhans cells in? what are they derived from? how can you identify them?

Answer 10

Derived from bone marrow and are in the stratum spinosum. The are intensely basophilic

Question 11

Where are merkel’s cells located? how can you identify them?

Answer 11

stratum basale and they are black

Question 12

What are the three main types of skin cancer?

Answer 12

1. Basal cell carcinoma (most common)
2. squamous cell carcinoma
3. malignant melanoma (most deadly)

Question 13

What are pacinian corpuscles? where are they found?

Answer 13

large ovoid structures deep in the hypodermis/dermis that are used for detecting pressure & vibration

Question 14

What are meissners corpuscles? where are they found?

Answer 14

USed for detecting light touch located in ther dermal papillae of thick skin. MAde from flattened schwan cells

Question 15

What are the four epidermal skin appendages?

Answer 15

1. hair follicles, hair
2. eccrine sweat glands
3. apocrine sweat glands
4. sebaceous glands

Question 16

Compare and contrast Eccrine vs apocrine glands

Answer 16

Eccrine are widely distributed whereas apocrine are in your arm pits and pubic region. “stank” or offensive odor is generated from bacterial involvent associated with protein filled secretions from the apocrine glands