Why do we break the into "systems" when discussing it? why don't we just talk about the entire body all at once?

The body consists of various organ system.

Further Explanation:

Our body is made up of organ systems. Each organ performs a particular function. These organs interacts and communicates with each other so that they can coordinate among themselves.

The different organ system of the body are:

1. Digestive system: Consists of oral cavity, stomach, small and large intestine. They are involved in the digestion of nutrients like carbohydrate, protein and lipids which is converted into smaller molecules like simple saccharide, amino acid and fatty acid respectively.

2. Respiratory system: Consist of trachea and lungs. They are involved in exchange of oxygen and carbon dioxide.

3. Circulatory system: Consists of heart and blood vessel. Transport of nutrient material throughout the body.

4. Excretory system: Kidney and urinary system. They removes out the waste material.

The function of individual system need to be understood very well so as to know which body part performs what kind of functions.  

The functioning of every organ and organ system is necessary for the survival of every individual.

Learn more:

1. Learn more about heart

2. Learn more about blood

3. Learn more about bloodstream

Answer Details:

Grade: CollegeBiology

Subject: Biology

Chapter: Organs and organ systems

Keywords:

Body, organ systems, organ, large intestine, digestion, nutrients, carbohydrate, protein, lipids, saccharide, amino acid, fatty acid , respiratory system, trachea, lungs, oxygen, carbon dioxide, circulatory system, heart, blood vessel, body, excretory system, kidney, urinary system.