<span>How many openings are in the digestive system of flatworms? Answer: 1
Flatworms digestive system is called 2-way which mean the same opening is used for eat and removing waste. That's why it only has one opening. Human system is one way since we eat from the mouth and remove waste from the anus.</span>
Correct matching of invertebrates and its characteristics are as follows:
Sponges are animals which have many cell but no mouth, muscles , heart or brain. They are sessile and can not move from place to place like other animals do, filter feeding animals with an asymmetrical body plan.
Cnidarians are the animals with radial symmetry and stinging cnidocyte cells. These animals consists a special cell cnida which functions in preying catch and defense. example- jellyfish, anemone.
Flatworms are the worm like animal which do not consist a body cavity or coelom. example- fluke and tapeworms.
Roundworms or threadworms are segmented worms that can live in water or land. They consist a body cavity and internal organs. examples- pinworms and hookworms.
Mollusks are the animals which consist mentle, foot and and sometimes a shell. example- octopus, squids.
Echinoderms are the animals which have radial symmetry and an endoskeleton made out of calcareous plate. These animals live only in marine environment.These animals lack circulatory and excretory systems.
Arthopods are the animals with jointed legs and an exoskeleton made out of chitin. example- spiders, shrimps and crabs.
In an ecosystem, two factors are being classified which are the abiotic and the biotic factors. Both of these factors play an important role in order to balance the ecosystem and maintain the harmony of the living things therein. The environment includes the abiotic factors which are the sunlight, weather, water, air, and all other factors which are not living but contribute to the growth and development of the living ones. For example, plants cannot live without water, sunlight and carbon dioxide. The effects that humans have on the environment is both good and bad. Humans also play an important role in maintaining the environment, and they also have the capability to endanger it.
