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IgorLugansk [536]
2 years ago
8

What surface cost the least fraction? a. Rock b. Grass c. Dirt d. Ice

Biology
2 answers:
devlian [24]2 years ago
8 0
B.grass because the mass of ice,rock,dirt is heavy to grass so grass would have the least fraction of surface cost.
Cerrena [4.2K]2 years ago
8 0
I think B becuase grass doesnt hurt u and all the other things they can hurt u
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Viruses spend time inside human cells, which protects any outer antigens from some of the aspects of the immune system. There are times when viruses are especially vulnerable during replication, but there are reasons they are harder than bacteria to target with these antireplication drugs: 1) unlike for most bacteria, the drugs need to be small enough to enter the human cell where the virus is replicating, 2) unlike for most bacteria, the drugs can't simply target a protein shared by most viruses; furthermore, many viruses hijack human proteins which cannot be targeted. Overall, there are comparatively few antiviral drugs compared to antibiotics because of the huge difficulty in obtaining selective toxicity. And 3) most drugs available target a certain step of viral replication for a certain family of viruses; however, by the time the patient shows symptoms, the virus has already created countless copies of itself or become latent in human cells, and at that point it is too late for most of the antiviral drugs to be super helpful since they target the replication itself. Even when a good antiviral drug is developed, most of them work only against a single species (or at best, a family) of viruses, which is not the case for most antibiotics.

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