Hunting the Invisible: teacher key

Germs, grade 9 edition, written for 9th grade. Pasteur, Koch, Semmelweis and Fleming each worked out something new about tiny living things and disease. Follow their experiments, then see how handwashing studies and antibiotic resistance work.

Read the book. Print this page for the key.

Questions and answers

1. What did Pasteur's swan-neck flasks show?
   • Air alone cannot create life (answer)
   • Wine can be made in a flask
   • Mold makes medicine
2. What did Semmelweis ask medical students to do in 1847?
   • Stop visiting mothers
   • Wash in chloride of lime first (answer)
   • Use microscopes
3. Why is the best handwashing time still not settled?
   • Studies counted microbes removed, not people kept healthy (answer)
   • Soap stopped working
   • No one has tested washing
4. Why does each use of an antibiotic help resistant bacteria spread?
   • It makes the drug stronger
   • It leaves resistant survivors to multiply (answer)
   • It teaches bacteria to hide
5. In this passage, what does a flask hold?
   • A liquid in a glass container (answer)
   • A kind of mold
   • A hospital clinic

Words

• pasteurization: heat-killing germs
• fermentation: yeast changing sugar
• phagocytosis: cell swallowing germs
• penicillin: mold medicine
• resistance: drug immunity