Q: What makes breathing difficult due to respiratory system disease? Choices: - weak lungs - slippery air passages - water in the lungs - narrow air passages A:
narrow air passages

Q: What part of the sweet potato store sugar from photosynthesis as starch? Choices: - plants - skin - shrubs - roots A:
roots

Q: What type of disease is caused by pathogens? Choices: - viral diseases - nervous diseases - autoimmune diseases - infectious diseases A:
infectious diseases