The immune system<span> is made up of a network of cells, tissues, and organs that work together to protect the body. One of the important cells involved are white blood cells, also called leukocytes, which come in two basic types that combine to seek out and destroy disease-causing organisms or substances.</span>
Answer:
Colloids or colloidal solutions are mixtures in which microscopically dispersed insoluble particles of one substance are suspended in another substance. The size of the suspended particles in a colloid can range from 1 to 1000 nanometers (10-9 meters).
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I think it is D. because the sun's radiant energy gives life to the earth life forms.
It is not possible for two species with the same niche to coexist. one species will eventually drive the other into extinction
