Via the blood, distributes oxygen and nutrients to all body cells and delivers wastes and carbon dioxide to disposal organs. Which system is described?

• A. Cardiovascular system
• B. Lymphatic system
• C. Endocrine system
• D. Digestive system

Answer: (A)

The main idea is how the blood serves as the transport system for the whole body. The cardiovascular system, made up of the heart, blood vessels, and blood, pumps oxygen and nutrients from the lungs and digestive organs to every cell, and it carries wastes like carbon dioxide to disposal organs such as the lungs and kidneys for elimination. Oxygen is carried by red blood cells and delivered as blood flows through capillaries to tissues, while nutrients move from the blood into cells to fuel their activities. Wastes are picked up from tissues to be disposed of. Other systems have related roles but don’t serve as the primary network for moving these materials throughout the body: the lymphatic system handles immune functions and fluid balance; the endocrine system distributes hormones via the blood but its purpose is signaling rather than broad nutrient distribution; the digestive system processes and absorbs nutrients but doesn’t act as the main highway that reaches every cell.