Health Ch. 13

When plaque hardens, it forms a crust-like substance called ______

A tooth is naturally protected from bacteria by ______

A protective layer of ______ covers the crown of a tooth.

The _____ is the visible portion of the tooth.

Functions of the skin include (select all that apply):

• protecting the body from pathogens.

• sensing pressure, pain, heat, and cold.

• controlling internal body temperature.

What is one way to keep the skin healthy?

• frequently touching the skin with the hands

• washing with strong soap several times a day

• choosing nonirritating skin-care products

• avoiding foods that are rich in vitamin A

A skin problem that is caused by a virus is

• eczema.

• athlete’s foot.

• warts.

• ringworm.

What can help control the spread of head lice?

• following a well-balanced eating plan

• frequently wearing hats

• frequently vacuuming at home

• using curling irons or hot combs

Which statement about the nails is false?

• Nails are made of dead cells containing keratin.

• Trimming toenails straight across helps prevent ingrown nails.

• Nails protect and support the fingers and toes.

• Keeping toenails long reduces the risk of nail infections.

When sound waves enter the ear, they cause the eardrum to

• stimulate receptor cells.

• send messages to the brain.

• vibrate.

• interpret sounds.