<span>The trait that is ancestral to all chordates is the presence of a notochord...the others are gill slits and nerve chord</span>
Answer: Sea walnuts are marine invertebrates. They belong to the genus Mnemiopsis.
Explanation:
These animals have stinging tentacles like jelly fish and they often cast up or come to the sea shores where if they come in contact with humans can harm them by stinging.
The barrier if kept along the side of the sea shore and not allowing humans to reach to the shore can help in preventing the harm from these animals. The introduction of the predatory animals in the sea can also help in reducing their population.
The three benefits for removing the sea walnut:
1. The population of other species will increase as sea walnut is an invasive species.
2. The balance of the marine ecosystem can be maintained.
3. Humans can be protected from the harm caused by these animals.
A control variable is a scientific experiment in which the experimental element is unchanged throughout the experiment
a control group is a group in an experiment that does not receive the treatment by the researchers (untouched by them) and used to see the changes between the controlled group and that of the group that received the vial
hope this helps
10. mouth
11. salivary glands
12. esophagus
13. stomach
14. small intestine
15. large intestine
