dermis and hair

skin pigment

caused by the interaction of the pigments in epidermis and blood flow in the dermis

2 types of pigments

• carotene: orange, yellow

• melanin: brown, yellow, brown, and black

melanocytes

cells that produce melanin

the amount of pigment influences what?

the skin color not the number of melanocytes

fingerprints:

• epidermal ridges:

projection of the stratum basale into the dermis that increase surface are between layers.

contours on the skin surface follow what?

the pattern = fingerprint

dermal papillae

dermal projections that are in between the dermal ridges.

structures of the dermis:

• sebaceous gland:

• associated with hair follicle

• secretes oily substance: sebum

• lubricates hair

• blocked = acne

• * any hair you have oil secretes

sweat glands (sudoriferous gland): 

• produces water and salts

• flush epidermal surface

merocrine glands:

• most common 

• secretion is mostly water with solutes

• cools body down, responds to temperature

apocrine

• develops scent as bacteria metabolize secretion

• stimulated with frightened, during pain, or during emotional distress

• found in genital area and axillae (arm pit)

• strongly influences by hormones

sensory structures of dermis:

• touch/pressure:

pacinian corpuscles/meisner’s corpuscles

temperature/pain:

free nerve endings