Chapter 5 Nail Structure and Growth

The ____ is the hard, protective plate that protects the tips of the fingers or toes.

Natural Nail

What part of the natural nail unit protects the tips of the fingers and toes?

Nail plate

Angela is training to be a cosmetologist. While she is working on a client, her manager stops her because she's about to clip too close to the eponychium. What might Angela have confused the eponychium for?

The nail cuticle

The natural nail itself is technically referred to as the ________.

Onyx

The _______________ is composed mainly of keratin.

Onyx

What are the characteristics of a normal, healthy nail?

Firm and flexible

What color is NOT normal for a healthy nail?

reddish

The natural nail unit includes which part of the finger?

The tip to the first knuckle

Which of the following is not a part of the natural nail unit?

Onyx

The lateral nail fold is also known as

Sidewall

The proximal nail fold is the entire flap of skin that covers what?

The matrix

The nail plate has approximately how many nail cell layers?

100

What is the water content of a healthy nail?

15 to 25 percent

What is the visible part of the matrix that extends from underneath the living skin?

lunula

Cuticle moisturizers are designed for all EXCEPT?

The cuticle

What is the slightly thickened layer of skin that lies between the fingertip and the nail plate's free edge?

The hyponychium

A ____ is a tough band of fibrous tissue that connects bones or holds an organ in place

Ligament

The _____ is the part of the nail plate that extends over the tip of the finger or toe

Free edge

What is the relationship between water content and the nail?

The lower the water content, the more rigid the nail.

What is the living skin that supports the nail plate as it grows toward the free edge?

Nail bed

What helps guide the nail plate along the nail bed as it grows?

The bed epithelium

Why must the hyponychium be treated gently?

If the hyponychium is damaged, an infection under the nail plate is possible.

The growth of the nail plate is affected by all of the following EXCEPT ______.

Exercise

A normal nail plate grows forward from the ___ and extends over the tip of the finger

Matrix

How would you compare the relationship between the matrix and the plate?

The length, width, and curvature of the matrix determine the thickness, width, and curvature of the nail plate.

What is the average rate of nail plate growth in normal adults per month?

1/10 to 1/8 inch per month

During what time of year do nail plates grow fastest?

Summer

Which fingernail grows the fastest?

Middle fingernail

Which nail grows the slowest?

Thumbnail

How would you compare fingernail and toenail growth?

Toenails are thicker than fingernails because the toenail matrix is longer.

How long does it take for toenail plates to be fully replaced?

9 to 12 months

How long does it take for fingernail plates to be fully replaced?

4 to 6 months

Which of the following groups of people would have the fastest-growing nails?

Children

During which scenario do nail growth rates increase dramatically?

Last trimester of pregnancy

Stephanie is pregnant. She is talking to her cosmetologist friend, Charlie, about how wonderful her prenatal vitamins have been for her hair and nail growth. What could Charlie tell Stephanie about her nail growth?

Nail growth rates accelerate during pregnancy, whether she is taking prenatal vitamins or not.

What is the relationship between nail cell production and plate growth?

The faster the nail cells are produced, the faster the plate will grow

How would you recommend clients make their plate grow thicker?

Nothing can help the nail plate grow thicker.