3/28 - Living Environment

This bacterial cell can now be used to produce

• the bacterial gene for insulin that can be inserted into humans

• human genes for enzymes that can be inserted into humans

• insulin that can be used by humans

• enzymes necessary to treat human diseases

Fungi are decomposers that play an important role in the maintenance of an ecosystem. The role of fungi is important because they

• synthesize energy-rich compounds that are directly used by producers

• break down materials that can then be used by other organisms

• limit the number of plants that can perform photosynthesis in an area

• are competitors of other consumers such as herbivores

In 2011 and 2012, scientists working on the Banana River in Florida recorded a dramatic increase in the number of manatee deaths. Over the past 50 years, this area has also seen the human population increase by more than 500,000 people. It is believed that pollution from numerous sewage tanks leaked into the water, eliminating the manatees’ food source, replacing it with an alga that is toxic to the manatee. This is an example of

• a natural cycle in an ecosystem

• the effect of increased biodiversity on an ecosystem

• direct harvesting in an ecosystem

• human actions altering ecosystems with serious consequences