endocrine system skeletal system integumentary system lymphatic system
I gave my students this multiple choice question: The cellular membrane surrounds every human cell. The membrane protects the cell and transmits information about the cell's surroundings to organelles inside the cell. What organ system provides a similar function in the human body?

Only one answer is correct among these 4 choices:
- endocrine system
- skeletal system
- integumentary system
- lymphatic system

Could you tell me which one is correct?

integumentary system