To maintain a stable environment.<span />
Freshwater ecosystems have been modified by the creation of dams and the withdrawal of water for human use, which have changed the flow of many large river systems. This in turn has had other effects such as reducing sediment flows, the main source of nutrients for estuary ecosystems.
Within terrestrial ecosystems, more than half of the original area of many types of grasslands and forests has been converted into farmland. The only types of land ecosystems which have been changed relatively little are tundra and boreal forests, but climate change has begun to affect them.
The distribution of species on Earth is becoming more homogenous. By homogenous, we mean that the differences between the set of species at one location on the planet and the set at another location are, on average, diminishing. The natural process of evolution, and particularly the combination of natural barriers to migration and local adaptation of species, led to significant differences in the types of species in ecosystems in different regions. But these regional differences in the planet’s biota are now being diminished.
Non-native species
Figure 1.7 Non-native species
Two factors are responsible for this trend. First, the extinction of species or the loss of populations results in the loss of the presence of species that had been unique to particular regions. Second, the rate of invasion or introduction of species into new ranges is already high and continues to accelerate apace with growing trade and faster transportation. (See Figure 1.7.) For example, a high proportion of the roughly 100 nonnative species in the Baltic Sea are native to the North American Great Lakes, and 75% of the recent arrivals of about 170 nonnative species in the Great Lakes are native to the Baltic Sea.
When species decline or go extinct as a result of human activities, they are replaced by a much smaller number of expanding species that thrive in human-altered environments. One effect is that in some regions where diversity has been low, the biotic diversity may actually increase—a result of invasions of nonnative forms. (This is true in continental areas such as the Netherlands as well as on oceanic islands.)
hope this helps im not sure it will
A(n) <u>gene</u> is a sequence of organic nitrogen base pairs that codes for a polypeptide or a protein.
What is polypeptide?
Peptides are made up of short chains of amino acids joined together by peptide bonds. The word "peptide" comes from the Ancient Greek word "peptós," which means "digested." Oligopeptides, which comprise dipeptides, tripeptides, and tetrapeptides, are chains of fewer than twenty amino acids.
A polypeptide is a peptide chain that is longer, continuous, and unbranched.
Therefore, along with nucleic acids, oligosaccharides, polysaccharides, and others, peptides belong to the large chemical families of biological polymers and oligomers.
A protein is a polypeptide that has more than 50 amino acids, on average. A protein is made up of one or more polypeptides that are structured in a biologically useful manner. Proteins are frequently coupled to other proteins, other macromolecules like DNA or RNA, or complex macromolecular assemblies.
to know more about polypeptide
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Answer:
No, plants don't grow in any area because they know they are going to be eaten by animals.The vegetation is just determined by the climates and the environment. You could have a whole forest in your backyard if it wasn't for structures being build and trees being cut down.
Explanation:
