The tiny pore drawn here was photographed on the underside of a leaf, with the cells around it labelled. During a dry afternoon the plant must shut this por...
Question 1 Report
The tiny pore drawn here was photographed on the underside of a leaf, with the cells around it labelled. During a dry afternoon the plant must shut this pore to hold on to water. Which labelled pair of cells carries out the closing?
Answer Details
Each stoma is bordered by a pair of guard cells, and it is these cells that open and close the pore by changing shape as they gain or lose water. On a dry afternoon the guard cells lose water, become flaccid, and close the stoma to conserve water. Palisade cells carry out photosynthesis, root hair cells absorb water from soil, and xylem vessels transport water; none of these control the opening and closing of the stoma.
Download The App On Google Playstore
Everything you need to excel in your exams
