Cells are organized into tissues, which are then organized into organs, and are finally organized into organ systems.
Systems are composed of different organs working together to carry out a common function or purpose. For example, the stomach, pancreas, intestines, are organs that are part of the digestive system, which breaks down the food we eat to give nourishment to our body.
Similarly, organs are made up of similar tissues carrying out a common function, and tissues are made up of cells of the same kind or type, also carrying out a common function or purpose.
The answer is false there were only types the saurischians and the ornithischians.
Ecosystems maintain themselves by cycling energy and nutrients obtained from external sources. At the first trophic level<span>, </span>primary producers<span> (plants, algae, and some bacteria) use solar energy to produce organic plant material through photosynthesis. Herbivores—animals that feed solely on plants—make up the second trophic level. Predators that eat herbivores comprise the third trophic level; if larger predators are present, they represent still higher trophic levels. Organisms that feed at several trophic levels (for example, grizzly bears that eat berries and salmon) are classified at the highest of the trophic levels at which they feed. Decomposers, which include bacteria, fungi, molds, worms, and insects, break down wastes and dead organisms and return nutrients to the soil
I got this passage from Annenberg Learner
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