Answer:
When starfish were removed from their environment, the species richness of that area went down. This was because the starfish ate the mussels, and when the starfish were removed, the mussels became abundant and preyed on many of the other species.
This experiment showed that the starfish were a keystone species. A keystone species is a species that has a low biomass but a large impact on the community they are living in.
Plants inherit genes that enable them to produce chlorophyll, but this pigment is not produced unless the plants are exposed to light. this is an example of how the environment can influence on gene expression.
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Light has an important role in gene expression in plants by producing a number of light-induced changes. One of the examples of the light effects is that chlorophyll and the proteins required for assembling the photosynthetic apparatus are synthesized together with the enzymes needed for carbon fixation. Gene expression influenced by light includes the regulation at the level of transcription or, alternatively regulation of translation.</span>
The 'cheek' is the common name for the insect GENA.
The gena is located in the head area of insects. The gena forms the sclerotized area on each side of the head, below the compound eyes, which extends to the gular structure. The gena varies among species of insects.