Question

austin and marissa hypothesize that coneflower stomata use feedback loops to respond to moisture levels by opening when there is moisture present, and closing when there is no moisture present. which best describes the setup they should use to support their hypothesis? a. austin and marissa should observe the number of stomata on one leaf, mist the leaf with water, wait one hour, and count the number of stomata that have grown. b. austin and marissa should observe the number of open stomata on one leaf, mist the leaf with water, wait one hour, and count the number of open stomata again. c. austin and marissa should observe the number of stomata on one leaf, mist the leaf with water, wait one hour, and count the number of stomata that have disappeared. d. austin and marissa should observe the number of closed stomata on one leaf, mist the leaf with water, wait one hour, and count the total number of stomata.

Explanation:

The hypothesis is about stomata opening with moisture and closing without it. To test this, they should observe the change in the number of open stomata before and after adding moisture. Option B focuses on the number of open stomata before misting (moisture - addition) and after waiting an hour, which directly tests the hypothesis. Options A, C, and D are about the growth, disappearance, or total number of stomata rather than the opening - closing behavior related to moisture.

Answer:

B. Austin and Marissa should observe the number of open stomata on one leaf, mist the leaf with water, wait one hour, and count the number of open stomata again.