Question

question 13 (1 point)
in which phase of the hair growth cycle does the follicle canal shrink and detach from the dermal papilla?
o a anagen phase
o b nitrogen phase
o c telogen phase
o d catagen phase

question 14 (1 point)
each of the following is a layer of the hair shaft structure except
o a the cortex
o b the hair fiber
o c the medulla
o d the hair cuticle

question 15 (1 point)
which part of the living portion of the hair is defined as the structure in the skin or scalp that surrounds the hair root and anchors the hair in the skin?
o a the hair bulb
o b the dermal papilla
o c the arrector pili muscle
o d the hair follicle

Explanation:

Question 13

• Anagen phase: Active growth phase, not when follicle detaches.
• Nitrogen phase: Not a recognized hair - growth phase.
• Telogen phase: Resting phase, but detachment occurs in catagen.
• Catagen phase: Follicle canal shrinks and detaches from dermal papilla.

• Cortex: Middle layer of hair shaft.
• Hair fiber: Not a distinct layer; hair shaft is made of fibers.
• Medulla: Inner layer (in some hairs).
• Hair cuticle: Outer layer.

• Hair bulb: Base of hair follicle where growth occurs.
• Dermal papilla: Supplies nutrients, not the surrounding structure.
• Arrector pili muscle: Causes hair to stand up.
• Hair follicle: Surrounds hair root and anchors hair.

Answer:

d. catagen phase

Question 14