Question 28

The circulatory system transports a metabolic waste product from the body to the lungs.

The circulatory system is responsible for transporting carbon dioxide, a metabolic waste product, from the body tissues to the lungs for exhalation. This process is essential for maintaining the body's homeostasis and is a key function of the circulatory system.

A) The circulatory system

This option is correct because the circulatory system carries carbon dioxide from the cells, where it is produced as a waste product of metabolism, to the lungs. In the lungs, carbon dioxide is exchanged for oxygen, which is then transported back to the body.

B) The excretory system

While the excretory system does play a role in removing waste products from the body, it primarily focuses on the elimination of liquid waste through urine and does not transport gases like carbon dioxide to the lungs. Therefore, this option is incorrect in the context of transporting metabolic waste to the lungs.

C) The endocrine system

The endocrine system is responsible for hormone production and regulation, and it does not have a role in the transport of metabolic waste products like carbon dioxide. Thus, this option is not relevant to the question.

D) The digestive system

The digestive system is involved in the breakdown and absorption of nutrients from food, but it does not transport metabolic waste products to the lungs. Instead, its main function is to handle solid waste elimination. Therefore, this option is also incorrect.

Conclusion

The circulatory system is uniquely tasked with transporting metabolic waste products, such as carbon dioxide, to the lungs for exhalation, making it the correct answer. Other systems like the excretory, endocrine, and digestive systems do not fulfill this specific function, highlighting the singular role of the circulatory system in gas exchange and waste removal.