Skin is the Largest barrier agaisnt Pathogens which include Bacteria which cause infections.
Answer:
Viscosity
Explanation:
Ive had this question on quizzes many times. And viscosity was the answer.
The reason for why celery stalk firms in water is because of its hypotonic environment and the salt content transfers into the celery stalk which makes the cell firm and significantly bigger.
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a. radioactive isotopes. They use radioactive Phosphorus-32 as labels on a phage (bacteriophage) DNA that infects E. coli. Their experiment showed that the radioactive isotopes were only seen in E.coli and not in the phage.</span>
<span>Echinoderms are marine invertebrates, they dwell under the sea unlike that of others that mostly live in land.
<em>Hope this helps:)</em></span>