c) Longitudinal ridging is seen in raynaud's disease.

d) Cuticle becomes ragged in dermatomyositis.

e) Nail fold telangiectasia is a sign in dermatomyositis ,systemic sclerosis and SLE.

4) Structure and consistancy:-

a) Fungal infection of nail causes discolouration,deformity,hypertrophy and abnormal brittleness.

b) Thimble pitting of nail is charecteristic of psoriasis ,acute eczema and alopecia aereata.

c) The inflamation of cuticle or nail fold is called paronychia.

d) Onycholysis is the seperation of nail bed seen in psoriasis,infection and after taking tetracyclines.

e) Destruction of nail is seen in lichen planus,epidermolysis bullosa.

f) Missing nail is seen in nail patella syndrome.It is a hereditary disease.

g) Nails become brittle in raynauds disease and gangrene.

h) Falling of nail is seen in fungal infection,psoriasis and thyroid diseases.

5) Growth:-

Reduction in blood supply affects the growth of nails. Nail growth is also affected in severe ilness. when the disease disappears the growth starts again resulting in formation of transverse ridges.These lines are called Beau's lines and are healpful to date the onset of illness.