In the latter case the resistance is caused by dissipation of mechanical energy when the configuration or the direction of flow is sharply changed, by the formation of vortices and secondary flows as a result of the flow breaking away, by the centrifugal forces, etc.
Animals depend on plants for food as plants produce food and energy which animals can't, so, herbivores eat plants to get energy, carnivores eat herbivores and other carnivores for energy and omnivores eat all four, plants, herbivores, carnivores and also other omnivores for energy.
Plants provide shelter for animals and they make oxygen for the animals to live. When animals die they decompose and become natural fertilizer plants. Plants depend on animals for nutrients, pollination and seed dispersal. Plants are also useful for animal home because many animals live around plants. Why do animals depend on plants Plants give animals the food and shelter they need. Herbivores, which are plant eating animals, rely on plants to provide them with a regular source of food. They also provide shelter to may animals, both large and small. Bibliography