Integument

2. Contains keratohyalin granules; squamous, live cells.
5. Smooth muscle responsible for "goosebumps."
6. Common, arises from the basal layer.
7. Produces keratin, forms the water barrier, produces Vitamin D3.
9. Thermoregulation; secretes watery and proteinaceous components via merocrine secretion.
11. Originates from the stratum spinosum.
12. Several cell layers with desmosomes ("spines").
14. Dead cells, stains lightly.
16. Basal-most layer, mitotically active cells, contains hemidesmosomes.
17. Neural crest-derived; produces melanin for UV protection.
19. Thick, dense irregular connective tissue with collagen bundles.
20. Contains adipose tissue for insulation, smooth, and skeletal muscles.

1. Thin, loose connective tissue without collagen bundles.
3. Found in areas like the axilla; associated with hair follicles, secrete pheromones.
4. Secretes sebum via holocrine secretion; associated with hair follicles.
8. Monocyte-derived antigen-presenting cells.
10. Keratinized, dead cells filled with lipids for water impermeability.
13. Sensory mechanoreceptor cells in the stratum basale.
15. Contains dermal papilla and matrix cells.
18. Derived from melanocytes; highly aggressive.