Final answer:
Lymphatic capillaries originate in the tissue spaces between cells, where they collect interstitial fluid to form lymph and are distributed in most tissues, except for certain areas like the central nervous system and bone marrow.
Step-by-step explanation:
Lymphatic capillaries originate in the tissue spaces between cells. These capillaries, also known as terminal lymphatics, are crucial for the transport of interstitial fluid, which enters the lymphatic system to become lymph fluid. They are widely distributed throughout most tissues and are found entwined among the arterioles and venules in the body's soft connective tissues. An interesting fact about these capillaries is that in a single day, they can absorb about 20.4 liters of fluid from the tissues. Some areas, such as the central nervous system, bone marrow, bones, teeth, and the cornea of the eye, are exceptions and do not have lymphatic vessels. Lymph fluid that leaks out of the capillaries into the spaces between cells is collected by these lymphatic capillaries and is circulated within the vessels of the lymphatic system.