The iliac crest is easily palpated from the bodyâs exterior, making it an easily identifiable landmark. The iliac crest also lends itself to bone grafting and bone marrow transplants thanks to its proximity to the bodyâs surface and the large amount of bone tissue and red bone marrow found in the ilium.
Ecosystems have an atmosphere, soil, light, heat, water and living  organisms. The living organisms in an ecosystem can include plants,  animals or both.it is formed by livi â¦ ng non living thing.ll ecosystems must have a producer. A producer is a plant that can make its own energy (autotrophic). Th â¦ en, primary consumers eat the producer, taking 10% of the energy produced in the previous organism for itself. This is a small ecosystem, but an ecosystem nonetheless.
Marine ecosystem. Marine ecosystems are among the largest of Earth's aquatic ecosystems. Examples include salt marshes, intertidal zones, estuaries, lagoons, mangroves, coral reefs, the deep sea, and the sea floor. They can be contrasted with freshwater ecosystems, which have a lower salt content. Marine waters cover two-thirds of the surface of the Earth. Such places are considered ecosystems because the plant life supports the animal life and vice versa. See food chains. Marine ecosystems are essential for the