(Solved): 3. These organisms turn dead material into soil: _decomposers 4. A food _web shows food chain overl ...

3. These organisms turn dead material into soil: _decomposers 4. A food _web shows food chain overlap. 5. A food chain shows each organism occupies a different trophic level, which is defined by the number of energy transfer. 6. In a food chain, each organism occupies a different trophic level , defined by how many energy transfers separate it from the basic input of the chain. 7. Primary consumers are usually they may be algae eaters or bacteria eaters. , plant-eaters, though 8. Decomposers are sometimes found at trophic level. As a group, they eat dead matter and waste 9. An consists of a community of organisms together with their physical environment. 10.An ancestor shared by two or more descendant species is termed as 11. Ecosystems can be of different sizes and can be marine, aquatic, or terrestrial. Broad categories of terrestrial ecosystems are called 12.As a reminder, a community consists of all the populations of all the species that live together in a particular area. The concepts of ecosystem and community are closely related-the difference is that an ecosystem includes the physical environment, while a community does not. In other words, a community is the , or living, component of an ecosystem. In addition to this biotic component, the ecosystem also includes an component-the physical environment. 13. The process by which modern organisms have descended from ancient organisms over time 14. Some ecosystems are marine, others freshwater, and others yet terrestrialland based. ecosystems are most common on Earth, as oceans and the living organisms they contain cover $75\%$ of the Earth's surface. ecosystems are the rarest, covering only $1.8\%$ of the Earth's surface. Terrestrial, land, ecosystems cover the remainder of Earth. 15. is a difference between traits in individuals of the same species. 16. is recycled through Darth's ecosystems-though it may move from one ecosystem to another as it does when nutrients are washed away into a river. The same atoms are used over and over again, assembled into different chemical forms and incorporated into the bodies of different organisms. 17.As an example, let's see how nutrients move through a terrestrial ecosystem. A land plant takes in carbon dioxide from the atmosphere and other nutrients, such as nitrogen and phosphorous, from the soil to build the molecules that make up its cells. When an animal eats the plant, it uses the plant's molecules for energy and as building material for its own , often rearranging atoms and molecules into new forms. 18. When plants and animals carry out cellular respiration - , carbon dioxide is released into the atmosphere. Similarly, when they excrete waste or die, their chemical compounds are used for energy and building material by bacteria and fungi. These decomposers release simple molecules back into the soil and atmosphere, where they can be taken up a new in the next round of the cycle. 19. A trait that improves an organism's ability to survive ad reproduce in an environment is termed as 20.The ability of an organism to survive and reproduce is known as 21. Darwin's theory was based on the mechanism of , which explains how populations can evolve in such a way that they become better suited to their environments over time. 22. selection is a selective breeding of organisms to promote the appearance of desirable traits in offspring. 23. drit is a mechanism of evolution in which allele frequencies of a population change over generations due to chance 24. A biological consists of all the populations of different species that live in a given area. Community ecologists focus on interactions between populations and how these interactions shape the community. T or F 25. A is a group of organisms of the same species that live in the same area at the same time. Population ecologists study the size, density, and structure of populations and how they change over time. T or F 26. The biosphere does not consist of all the ecosystems on Earth, considered together. $T$ or $\mathrm{F}$