Body organs, nutrient needs

Our vital organs, glands, bones, ligaments, muscles, and other tissues of the body each have their own special nutritional needs (see Table 1.1). People s nutrient needs may be siinilar in many respects, but each person differs regarding the exact amounts of nutrients needed and may require special supplements to catch... 

The science of nutrition is an applied field that focuses on the study of food, water, and other nutrients and the ways in which living organisms utilize them. Nutrition scientists use the principles of nutrition to obtain answers to questions that have a great deal of practical significance. For example, they might try to determine the proper components of a sound diet, the best way to maintain proper body weight, or the foods and other nutrients needed by people with specific illnesses or injuries. 

The amount of nutrient degradation and ATP synthesis have to be continually adjusted to the body s changing energy requirements. The need to coordinate the production and consumption of ATP is already evident from the fact that the total amounts of coenzymes in the organism are low. The human body forms about 65 kg ATP per day, but only contains 3-4 g of adenine nucleotides (AMP, ADP, and ATP). Each ADP molecule therefore has to be phosphorylated to ATP and dephosphory-lated again many thousand times a day. 

Malnutrition is the condition that develops when the body does not get the right amount of the vitamins, minerals, and other nutrients it needs to maintain healthy tissues and organ function. 

Living cells do not increase their internal disorder when they consume and metabolize nutrients. The organism s surroundings increase in entropy instead. For example, the food molecules that humans consume to provide the energy and structural material needed to maintain their complex bodies are converted into vast amounts of disordered waste products (e.g., C02, H20, and heat) that are discharged into their surroundings. 

When organisms (including humans) take in more nutrients than are needed for energy requirements, the excesses are not excreted they are converted first to fatty acids and then to body fat. Most of the conversion reactions take place in the liver, adipose tissue, and mammary glands. The mammary glands become especially active in the process during lactation. 

---