The principal component of the dermis is collagen, predominantly Type I.

(a)  

Fingernails take around 12 18 months to replace a complete nail plate, while toenails grow slower.

(a)  

Pale skin has fewer, smaller melanocytes, while darker skin has more abundant, larger ones.

(a)  

On the palms and soles, there is a pale clear to pink layer above the granular layer called the stratum lucidum .

(a)  

Ideal illumination for examination

(a)  

This effect modifies the color of the skin and of lesion by selective scattering of light waves of different wavelengths

(a)  

This device is valuable for the diagnosis of some types of tinea capitis , tinea versicolor, and erythrasma .

(a)  

This sign is elicited by continuous rubbing, eventually forming a wheal.

(a)  

Lesions in a line

(a)  

Lesions may form a complete circle with normal-appearing skin centrally

(a)  

Lesions may form a portion of a circle

(a)  

Lesions composed of several intersecting portions of circles

(a)  

If the eruption is not straight but does not form parts of circles,

(a)  

Round lesions may be small, like drops, ;

(a)  

Larger coin-like lesions

(a)  

Pinpoint bleeding at the tops of ruptured capillaries with

forcible removal of outer scales from a psoriatic plaque

(a)  

Firmly stroking unaected skin produces a wheal along

the shape of the stroke within seconds to minutes

(a)  

Lateral pressure on unblistered skin with resulting shearing

of the epidermis

(a)