Because the tools to see them had not been invented.
Humans are most closely related to chimpanzees in terms of evolutionary history.
No, humans are not the most abundant organisms on Earth. Microorganisms such as bacteria and archaea are the most abundant and diverse organisms on the planet. Humans make up only a small portion of the total biomass on Earth.
No, most microorganisms are harmless and do not cause disease. Only a small percentage of microorganisms are pathogenic and have the potential to cause disease in humans, animals, or plants. Many microorganisms are beneficial to human health and play important roles in various ecosystems.
Sanitization reduces the number of microorganisms to a safe level, disinfection kills most but not all microorganisms, and sterilization kills all microorganisms. Sterilization is the most effective in killing microorganisms, followed by disinfection, and then sanitization.
Sanitization reduces the number of microorganisms to a safe level, disinfection kills most microorganisms but not all, and sterilization kills all microorganisms. Sterilization is the most effective in killing microorganisms, followed by disinfection, and then sanitization.
I am most certainly unaware of this answer
Some microorganisms are parasites, some parasites are microorganisms. However some parasites are very large, for example tapeworms have been found that were 60 feet long. Also most microorganisms are not parasites.
stone knaping
Sanitation involves cleaning to remove dirt and debris, disinfection kills most but not all microorganisms, and sterilization kills all microorganisms. Sterilization is the most effective in eliminating harmful microorganisms, followed by disinfection, and then sanitation.
The most genetically diverse populations of humans can be found in Africa, where there is a wide range of genetic variation due to the continent's long history of human evolution and diverse populations.
Sanitation involves cleaning to remove dirt and debris, disinfection kills most harmful microorganisms, and sterilization eliminates all microorganisms. Sterilization is the most effective in eliminating harmful microorganisms, followed by disinfection, and then sanitation.
Anaerobic respiration is most common in microorganisms.