It mutates because you are immune, but yes it mutates and gets a new trait to trick your body into letting it in.
Answer: d. all of the above
Renewable resources are those which can be replenished or reproduced at a faster rate. But heavily decrease in the volume of these resources sometimes cannot be compensated.
a. Loss of animal species: Hunting and poaching of animal species has limited the population of endangered species to derive valuables like horns, skins from these animals for human use.
b. Land degradation: Landmass occupied by natural forests and other natural biomes are cleared for human use like agriculture, mining, urban development. These lands are loosing their natural potential and are treated as waste lands.
c. Lower availability of fresh water: Water from water bodies like lakes, rivers, groundwater, ponds are polluted by industrial, agricultural wastes making water unfit for human use. Groundwater are pumped out to maximum amount but the same level cannot be maintained by natural sources of water such as rain, agricultural field irrigation, river or any other means therefore, limiting the level of water in grounds.
Activation of muscle contraction could be a speedy event that's initiated by electrical activity within the surface membrane and transversal (T) tubules. This can be followed by unharness of metal<span> from the inner membrane system, the sarcoplasmic reticulum.
</span>Nervous stimulation causes a depolarization<span> of the muscle membrane (sarcolemma) </span>that<span> triggers </span>the discharge<span> of </span>calcium<span> ions from the sarcoplasmic reticulum.</span>
ground water forms when water from the surface seeps into the ground