TASK DEFINITION: Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.
PROBLEM: Question: Viruses were assumed to exist before they were first seen with an electron microscope in which decade? Answer: 1930 ' s

SOLUTION: Viruses were assumed to exist before they were first seen with an electron microscope in the 1930s. Multiple hypotheses for viral origins have been proposed.

PROBLEM: Question: Unlike wild animals, what type of species are genetically uniform, making them more vulnerable to die-out from disease? Answer: domestic species

SOLUTION: Wild plants and animals maintain a valuable pool of genetic variation . This is important because domestic species are genetically uniform. This puts them at great risk of dying out due to disease.

PROBLEM: Question: The outer layer of what anatomical structure is so tough that it keeps out most pathogens? Answer: skin

SOLUTION:
This drawing shows that the skin has many layers. The outer layer is so tough that it keeps out most pathogens.