‘Growth Phase’ of the hair?
Correct Answer: Anagen
Description: Ans. A. AnagenHair Growth CycleScalp hair-follicles have a four phase cycle.Anagen (growth), Catagen (transition), Telogen (resting) and Exogen (hair-shaft evacuation).The Anagen Phase (growing phase)- During the process of folliculo-regenesis, the follicle + epithelial sheath + new hair shaft is recreated.- During its growth (anagen) phase the hair shaft continues to gain length for a period of 2-7 years.- Approximately 80-85% of hair follicles are in anagen.- Hair growth rates range from 0.5cm-1.45cm per month.The Catagen phase (involutionary phase)- mitosis ceases, the follicle enters a period of degeneration.- Catagen accounts for approximately 3% of hair follicles.- The Epithelial sheath shrinks forming a minute "club root" at the proximal end of the hair shaft.- Catagen lasts for approximately 10-20 days.The Telogen Phase (resting or dying phase)- approximately 12-20% of hair shafts are in the amitotic (resting) phase.- Eventually (up to 3 months) the hair shaft vacates the follicle.The Exogen Phase- in which the hair-shaft is evacuated.
Category:
Skin
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now