How does the tapeworm’s action inside the shrimp increase its chances of survival?

Infected shrimps have high level of lipids, fats and  antioxidants

Explanation:

When the brine shrimps get infected with parasite then their ability to survive in toxic water increases. Brine shrimps infected with tapeworms usually change their color and become red.  

The mining activities in surrounding area introduced harmful and toxic chemicals such as arsenic that has made the water habitat toxic for shrimps. Now it was found that shrimps with parasite increased in number as compared to shrimps without parasite. This is so because worm infected shrimps have more droplets of lipids — fats — in their tissues that helped them to sock away arsenic. Along with lipid fats infected brine shrimp also produced more antioxidants than the non-infected ones and hence the stress on cell reduced.

Generally infection by parasite is not considered as good but sometimes parasitic infection helps their host to survive.

Tapeworm's are the parasite which infects shrimp and increases its chances of survival. Tapeworm produces antioxidants inside the shrimp which reduces effects of stress on cells. tapeworm also produces lipid droplets that helps brine shrimp to survive water in water polluted with toxic arsenic.

Hence, Tapeworm's boost ability of shrimp to survive in water filled with toxic arsenic.

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