Answer:
the answer is the second one
In eukaryotic cells the DNA can be found in the nucleus mainly. so DNA replication takes place in the nucleus during the S phase of the cell cycle.
Also in eukaryotic cells there are mitochondria and chloroplasts (plants) and these have circular DNA and they also get replicated (according to their own mechanism).
Prokaryotic cells don't contain a nucleus. They do not contain DNA in the cytoplasm and thus the DNA replication will take place here.
I really hope this helps!
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.