Answer:
Mechanical barriers — which include the skin , mucous membranes , and fluids such as tears and urine — physically block pathogens from entering the body. Chemical barriers — such as enzymes in sweat , saliva , and semen — kill pathogens on body surfaces.
Eukaryotes are organisms who is containing a nucleus, cells and other organelles that are enclosed with membranes just like the prokaryotes does. Eukaryotes are able to reproduce asexually through the process of mitosis and sexually through the process of meiosis.
The answer to your question is bacteria
