Lecture 4 - Integumentary System

Question 1

Integument parts

Answer 1

-Epidermis, dermis
-Skin, hair, nails, sweat glands, sebaceous glands

Question 2

Integument functions

Answer 2

Protection, dehydration prevention, sensation, T regulation, vitamin D synthesis

Question 3

Epidermis

Answer 3

-Keratinized stratified squamous epithelium

Question 4

Epidermal layers

Answer 4

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-Stratum corneum
-Stratum lucidum
-Stratum granulosum
-Stratum spinosum
-Stratum basale

Question 5

Epidermis cells

Answer 5

-Dead keratinocytes
-Keratinocytes
-Melanocyte
-Merkel cell, sensory neuron (to dermis)

Question 6

Melanocyte

Answer 6

Stay near dermis, create melanin, causes differences in skin tones. Hemoglobin causes pink hue.

Question 7

Skin marks

Answer 7

-Nevus (mole/birthmark): overgrowth of melanocytes, harmless until mutation.
-Freckles: excessive melanocyte activity, not quantity.

Question 8

Dermis layers

Answer 8

-Papillary layer (areolar connective tissue)
-Reticular layer (dense irregular connective tissue)

Question 9

Scars

Answer 9

Damaged skin, replaced by fibrous tissue (collagen produced by fibroblasts)

Question 10

Wrinkles

Answer 10

-Loss of collagen / elastic fibers
-Decreased dermis thickness
-Less “spingy”

Question 11

Hypodermis (subcutaneous)

Answer 11

-Structure: areolar/adipose connective tissue, not part of integument
-Function: anchor skin to underlying structures, insulation, energy storage

Question 12

Nails

Answer 12

-Free edge
-Lunula
-Cuticle
-Nail body
-Nail root

Question 13

Hair structure

Answer 13

-Hard karatin
-Arrector pili muscle - pulls hair to stand it up, aka goose bump
-Layers: cuticle, cortex, medulla

Question 14

Hair types

Answer 14

Lanugo (fetal), vellus (fine), terminal (thicc)

Question 15

Hair function

Answer 15

Protection, sensation, reduce heat loss

Question 16

Hair growth

Answer 16

-2mm/week, variation to person to person

Question 17

Exocrine glands

Answer 17

-Sebacceous (oil) glands: sebum production
-Sudoriferous (sweat) glands:
–Eccrine glans: watery sweat, most numerous
–Apocrine glands: viscous sweat, in armpit, nipple, anal, genital areas.

Question 18

Acne

Answer 18

Overactive/plugged sebaceous ducts

Question 19

Burns

Answer 19

1st - damaged epidermis
2nd - damaged part of dermis
3rd - damaged entire epidermis and dermis

Question 20

Skin cancer

Answer 20

-Basal cell carcinoma: most common, least dangerous, in stratum basale
-Malignant melanoma: most deadly, from melanocytes, early detection is crucial