The lymphatic system is important for the transport of dietary:
A fats B carbohydrates C proteins D all of these E none of these
The correct answer and explanation is:
The correct answer is A) Fats.
The lymphatic system plays a crucial role in the transport of dietary fats, particularly in the form of chylomicrons. Chylomicrons are large lipoprotein particles that carry triglycerides (a type of fat), along with cholesterol and other fat-soluble vitamins, from the intestines into the bloodstream. This process is vital because fats are not easily absorbed directly into the bloodstream due to their large size and lipophilic (fat-loving) nature. Instead, they enter the lymphatic system through the lymph vessels.
After fats are digested in the small intestine, they are absorbed by enterocytes (intestinal cells). These cells reassemble the broken-down fats into triglycerides and package them into chylomicrons. The chylomicrons then enter the lymphatic capillaries called lacteals, which are specialized vessels in the villi of the small intestine. From there, they travel through the lymphatic system and eventually drain into the venous blood circulation at the thoracic duct, which connects to the subclavian vein.
Once in the bloodstream, the fats are transported to various tissues, including adipose tissue (for storage) and muscle cells (for energy use). The lymphatic system, therefore, is essential for the efficient absorption and distribution of fats and fat-soluble nutrients.
While carbohydrates and proteins are essential nutrients, they do not require the lymphatic system for their transport. Carbohydrates are absorbed directly into the bloodstream from the small intestine via the portal vein, and proteins are similarly absorbed and transported via the bloodstream. Hence, the lymphatic system is mainly involved in the transport of fats and fat-soluble substances.