The human immune system detects the presence of pathogens using pattern recognition receptor molecules that bind to common components of pathogens, such as peptidoglycan polymers in cell walls and the flagellin protein of bacterial flagella, known as pathogen-associated molecular patterns, or PAMPs. These receptors are effective becauseGroup of answer choicesthey detect only human immune molecules. they result in rapid evolution of the host immune system. they recognize evolutionarily conserved molecules that are structurally essential to the various bacteria that use them. PAMPs evolve more quickly than other pathogen molecules.

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.