What is the outermost layer of the hair shaft:
A) Scales
B Cortical fusi
C Cuticle
D) Cortex
The correct answer and explanation is:
The correct answer is C) Cuticle.
The cuticle is the outermost layer of the hair shaft. It consists of several layers of flat, scale-like cells that overlap, much like roof shingles. These cells are made of keratin, a tough, fibrous protein that provides strength and protection to the hair. The cuticle’s main function is to protect the inner layers of the hair, particularly the cortex and medulla, from physical damage and moisture loss. It also plays a role in the texture and shine of the hair, as the smoother the cuticle is, the shinier the hair will appear.
The cuticle cells are arranged in a way that allows them to protect the more fragile inner layers from external environmental factors, such as UV radiation and pollution, while also preventing the penetration of harmful chemicals. The scales of the cuticle can lift or lay flat depending on the condition of the hair. When the cuticle is in good condition and the scales are smooth, the hair looks healthy and shiny. However, when the cuticle is damaged or raised (due to factors like chemical treatments, heat styling, or environmental stressors), the hair can appear dull, rough, or frizzy, and is more prone to breakage.
It is important to care for the cuticle properly to maintain the hair’s health. Products like conditioners and oils help smooth the cuticle, sealing moisture in and keeping the hair hydrated. Additionally, minimizing heat styling and chemical treatments helps reduce damage to the cuticle, ensuring the inner layers remain protected and the hair retains its strength and appearance.