These skin microbes keep the immune system in a state of constant, ensuring that it's ready to react if the body really is at risk.

A. hazardous
B. balance
C. prevelance
D. surveillance

Which of the following are correct about Langerhans cells?

A. They are protective skin cells.
B. They can help trigger immune response.
C. They are mainly found in epidermis.
D. They are also called T-cells.

The skin carries out three key functions: protecting,, and sensing the world beyond its limits.

The epidermis is made up mainly of skin cells called keratinocytes. Keratin means (two words)

The English expression for 防水层 is.

Goosebumps appear when people feel cold, andcause hair to stand upright across the body. (two words)

Skin is the largest organ in our body.

A. 对
B. 错

Sebum is an oily substance that's secreted onto the skin's surface by sebaceous glands nestled inside the hypodermis.

A. 对
B. 错

Under warm conditions, the skin's sweat glands will secrete sweat via ducts onto the surface, transferring heat out of the body.

A. 对
B. 错

The average human has 5 million hair follicles embedded everywhere on the body.

A. 对
B. 错