The body needs calcium and phosphorous because phosphorus works with calcium to help build bones
The best answer is b. 4
The human heart has four chambers - two atria and two ventricles.
1. Right atrium - receives oxygen-poor blood from the body and pumps it to the right ventricle.
2. Right ventricle - pumps oxygen-poor blood to the heart.
3. Left atrium - receive oxygen - rich blood from the lungs.
4. Left ventricle - pumps oxygen rich blood to the body.
The heart is a muscular organ. It is about the size of a closed fist. It is located in the thoracic cavity. It is protected by the rib cage and is the major organ of the circulatory system.
Answer:
The world’s largest tropical rainforests are in Amazon basin in South America, lowland regions in Africa, and the islands off of Southeast Asia.
Answer:
The autonomic nervous system
Explanation:
The autonomic nervous system also called the vegetative nervous system is part of the peripheral nervous system which inervates smooth muscle and glands. Thus, it directly affects the function of internal organs and regulates functions such as the heart rate, digestion, respiratory rate, urination etc. This nervous system control is unconscious.
The autonomic nervous system is divided into: the sympathetic nervous system, the parasympathetic nervous system and the enteric nervous system.