Question

In C3 plants the conservation of water promotes _____.

a.photosynthesis
b.a shift to C4 photosynthesis
c.the opening of stomata
d.photorespiration
e.the light reactions

Answer 1

In C3 plants, the conservation of water leads to photorespiration because in conditions where plants close their stomata to save water, CO2 cannot be utilized effectively, and plants begin to fix oxygen instead, initiating photorespiration.

Step-by-step explanation:

In C3 plants, the conservation of water promotes photorespiration. This is because during periods of drought or high temperatures, plants close their stomata to conserve water. However, when the stomata are closed to save water, CO2 levels within the leaf drop, and O2 levels rise. As a result, the enzyme Rubisco begins to fix O2 instead of CO2, initiating photorespiration instead of the normal photosynthesis process. Moreover, plants have developed adaptations to conserve water; for example, desert plants like cacti can fix CO2 at night when temperatures are lower, reducing water loss through transpiration. Overall, conserving water is critical in harsh environments to help the plants survive extreme conditions.

Answer 2

The correct answer is d. photorespiration

Step-by-step explanation:

In the C3 plant, the Rubisco enzyme is important that fix CO2 into organic molecule by binding with CO2. Rubisco can also bind to oxygen when the oxygen concentration increases in cells which leads to the loss of fixed CO2 and waste of energy which is called photorespiration.

So when stomata are open CO2 comes in and O2 goes out of the cell which maintains the high CO2 concentration in the cell but during hot days C3 plants close stomata to prevent water loss.

So closing of stomata decrease the intake of CO2 and increase the oxygen concentration inside the cell. So in increased temperature and high oxygen concentration, the rubisco enzymes bind to O2 and promote photorespiration.