Though metabolism doesn't consist solely of the reactions that burn nutrients like carbohydrates, fats and protein, these are perhaps the most widely known of the metabolic reactions. Your metabolism, however, actually includes every chemical reaction that takes place in your body, Drs. Mary Campbell and Shawn Farrell explain in their book "Biochemistry." Some of these reactions burn molecules to produce energy, while others use energy to make larger molecules that the cells use for a variety of purposes, both functional and structural.

The cardiovascular system consists of the heart, blood vessels and blood. It's a relatively simple -- though critically important -- body system, in that it operates much like a pump and series of pipes through which water might move. The purpose of the system is to circulate oxygen to your body cells, but also to circulate nutrients. Your blood then returns the waste products -- including carbon dioxide -- of various metabolic reactions to the lungs and to excretory organs, Dr. Laurlaee Sherwood explains in her book "Human Physiology."

Anatomy & Physiology - Body Systems

Cardiovascular
Digestive
Endocrine
Muscular
Neurological
Respiratory
Skeletal
The Cardiovascular System

The branches of science that will help you understand the body parts and functions are anatomy and physiology. Anatomy deals with the study of the human body (the component parts, structure and position) and physiology the study of how the body functions.

Body Systems

The body comprises of a number of systems including the: Cardiovascular system, Digestive system, Endocrine system, Muscular system, Neurological system, Respiratory system and the Skeletal system.

The Cardiovascular System

The cardiovascular system comprises of the heart, blood, blood vessels and lymphatic system.

Heart

The function of the heart is to pump