Metaphase is the stage in which the "crossing over" occurs.
As we know chromosomes carry genetic information. This crossing over process happens in eukaryotic cells and occurs during the mitosis phases of cell division.
Hopefully this helped.
The correct answer to the question stated above is the first option: <span>an instinctive behavior was tied to a different stimulus.
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Pavlov's experiment was a typical case of classical conditioning because an instinctive behavior was tied to a different stimulus.
The right options are;
are disease-causing microorganisms
can be fatal
A pathogens is any substance or organism especially microorganisms that are capable of causing diseases. Pathogens include; bacteria, viruses, protozoa or fungi. Microorganisms are not considered to be pathogenic until they have reached a population size that is large enough to cause disease. Pathogens can be fatal and can be treated. Pathogens are diverse and they occupy essentially every environment.