The answer for this question would be Integument, digestive, respiratory and urogenital.
The largest system that contact with the external environment would be integument and digestive. That makes two system has normal flora of microbes and not sterile like the other systems. Normal flora of microbes will prevent the pathogen microbe grows so it gives some benefit.
Answer:
d
Explanation:
prokareyote or bacteria does not have a nucleus.
Some plants are able to withstand extreme weather conditions
The answer is endothermic.
Endothermic reactions are reactions that need energy to form a product.
Exothermic reactions are reactions that release energy.
Photosynthesis is a process in which energy of sunlight is used to convert carbon dioxide and water into glucose and oxygen. Hence, the energy of sunlight is needed for photosynthesis. So, photosynthesis is endothermic.