Answer:
Microorganisms are helpful to plants or animals in the following ways.
1) Some microorganisms are decomposers such as bacteria and fungi etc which decompose dead bodies of plants and animals and releases nutrients which is used by the plants for its growth.
2) Some microorganisms are used by the humans in making of different types of medicines.
3) Some microorganisms are used for making food such as bread and alcohol.
Pathogens are those harmful microorganisms which causes disease in plants and animals. They attack on the immune system of animals and make them sick. For example, fungi and viruses etc.
