AP BIOLOGY

Detailed explanation-1: -Plants Still Need to Perform Photosynthesis During Drought. Plants are green because they contain a green chemical called chlorophyll.

Detailed explanation-2: -Water stress reduced photosynthesis, initially as a consequence of stomatal closure, but after 3 days increasingly by inhibiting directly the photosynthetic capacity (mesophyll limitation).

Detailed explanation-3: -Water is necessary for photosynthesis, which is how plants use energy from the sun to create their own food. During this process, plants use carbon dioxide from the air and hydrogen from the water absorbed through their roots and release oxygen as a byproduct. This exchange occurs through pore-like stoma on the leaves.

Detailed explanation-4: -Water stress that induces a decrease in leaf water potential and in stomatal opening (Figure 1), leading to the down-regulation of photosynthesis-related genes and reduced availability of CO2, has been known as one of the major factors in the EL stress (Osakabe and Osakabe, 2012).

Detailed explanation-5: -Under long term water stress, plants might permanently wilt or stop growing; they may have diminished crops and discolored leaves, flower buds and flowers. Plants may eventually die. Bare spots will appear in ground covers. Water-stressed plantings may show the effects of weeds, insect pests, and diseases.