Plants and Snails Comprehension Check

The two tubes contain bromothymol blue. After 24 hours, what will the color of the water be in tube B?

• green (it won't change)

• yellow

• blue

• colorless

The two tubes contain bromothymol blue. The lights are off. After 24 hours, what will the color of the water be in tube C?

• green (it won't change)

• yellow

• blue

• colorless

The two tubes contain bromothymol blue. The lights are on. After 24 hours, what will the color of the water be in tube D?

• 
  

• green (it won't change)

• yellow

• blue

• colorless

Two snails and two Elodea sprigs are placed together in a tube containing a bromothymol blue solution. The tubes are put into a dark closet. After 24 hours, what will the color of the water be in tube A?

• green (it won't change)

• yellow

• blue

• colorless

You have an Elodea sprig in a test tube containing bromothymol blue. Then you watch it for several days. At what time of day will the oxygen level in the tube be the lowest?

• just before sunset

• midnight

• just before sunrise

• mid-afternoon