<span>Invertebrate<span>, </span>any animal that lacks a vertebral column, or backbone, in contrast to the cartilaginous or bony vertebrates. More than 90 percent of all living animal species are invertebrates. Worldwide in distribution, they include animals as diverse as sea stars, sea urchins, earthworms, sponges, jellyfish, lobsters, crabs, insects, spiders, snails, clams, and squid. Invertebrates are especially important as agricultural pests, parasites, or agents for the transmission of parasitic infections to humans and other vertebrates. Invertebrates serve as food for humans and are key elements in food chains that support birds, fish, and many other vertebrate species.Apart from the absence of a vertebral column, invertebrates have little in common. Indeed, they are distributed between more than 35 phyla. In contrast, all vertebrates are contained within a single phylum, the Chordata. (Phylum Chordata also includes the sea squirts and some other invertebrate groups.) Invertebrates are generally soft-bodied animals that lack a rigid internal skeleton for the attachment of muscles but often possess a hard outer skeleton (as in most mollusks, crustaceans, and insects) that serves, as well, for body protection.</span>
Invasive species are species that are not native to specific ecosystem,
but they have a capability to spread widely through the ecosystem, This way
they can threaten native species of the ecosystem or cause
environmental harm.
<span>After being introduced into the Black Sea, they greatly affect local
ecosystem. In the new area, they have no natural predators and are able to
spread. If they spread beyond the area they are introduced, they
become invasive species which can overgrow native biotopes and are
a great threat to the local biodiversity. This could lead to the extinction
of some native species.</span>
In the natural carbon cycle, there are two main processes which occur: photosynthesis and metabolism. During photosynthesis, plants use carbon dioxide and produce oxygen.
The scientific definition of evolution refers to changes in a species or population over time.
Evolution is a long-term process. It may take millions of years and several generation for an evolution to occur. The cause of evolution can be genetic as well as environmental. The evolution is a result of mutation. Evolution generally gives rise to new species, that is different from its ancestral population.
Population is a group of similar type of organisms. These organisms live in the same habitat, require same resources and have same kind of habits. The most essential criteria that defines a population is that the organisms of a population can mate with each other and produce offspring.
If it is more salty it means that the water is hypertonic to the hypotonic potato and if the water is less salty then the water is hypotonic to the hypertonic potato
