Koch’s Investigation of Anthrax

Anthrax that was killing cows and sheep. Koch was curious about the cause of the

disease.

Koch’s Experimental Step 1

In your science notebook, describe what Koch did in his first step.

Koch’s Observation

In your science notebook, record your observations.

Koch’s Experimental Step 2:

Koch’s Observation:

What can you infer from the observations of sick and healthy cows? Record your inference in your science notebook.

Koch’s Inference: the “rods” and “threads” cause anthrax.

What would be the next experimental step?

Record the experimental step in your science notebook.

Koch’s Experimental Step 3:

Koch’s Observation:

What can you infer from this observation?Record your inference in your science notebook.

Koch’s Inference: the mouse died of anthrax.

What would be the next experimental step?

Record the experimental step in your science notebook.

Koch’s Experimental Step 4:

tissue and blood from dead mouse spleen

Koch’s Observation:

What can you infer from this observation?Record your inference in your science notebook.

Koch’s Inference: the blood from the cow caused anthrax

in the mouse.

What would be the next experimental step?

Record the experimental step in your science notebook.

Koch’s Experimental Step 5:

Blood from cow died from anthrax

Koch’s Observation:

Blood and tissue from dead mouse spleen

What can you infer from this observation?Record your inference in your science notebook.

Koch’s Inference: the “rods” and “threads” are alive.

Koch’s Experimental Step 6:After transferring one drop of culture to a new slide and letting it sit each day for 8 days, Koch had a purified culture.

What would be your next experimental step?Record the experimental step in your science notebook.

Koch’s Experimental Step 7:

Purified culture

from Step 6

What can you conclude about the cause of anthrax?

Record in your science notebook.