Any two effects of gravitational force are as follows:
1. The Earth's gravitational force accelerates objects when they fall.
2. It constantly pulls, and the objects constantly speed up.
<u>Answer:</u>
<em>Enzyme activity decrease at these temperatures.
</em>
<u>Explanation:</u>
Photosynthesis is facilitated by the action of various enzymes and involves light and dark reactions. In <em>light reactions chlorophyll absorbs sunlight and creates ATP AND NADPH</em>. In dark reactions carbon is fixed using the <em>ATP and NADPH.
</em>
The efficiency of all these activities depends on the activity of enzymes which depends on the temperature. The optimum temperature range where the enzyme activity is optimal is about <em>10°c - 20°c</em>. At low temperatures and high temperatures enzyme activity is less efficient.
<em>At a temperature above 38°c and below 0°c enzyme activity decreases.
</em>
Nutrient Leaching
Leaching is the process where dissolved nutrients in the
soil profile moves downward with percolating water. It is the loss of
water-soluble plant nutrients from the soil. The nutrients that seep through
the rooting zone may be recycled if roots grow deeper.
Photorespiration limits casualty products of light reactions
that build up in the absence of the Calvin cycle. In many plants,
photorespiration is a problem because on a hot, dry day it can drain as much as
50% of the carbon fixed by the Calvin cycle. The closing of stomata reduces access to CO2
and causes O2 to build up. These conditions favor a seemingly not useful process
called photorespiration. In most plants
(C3 plants), initial fixation of CO2, via rubisco, forms a three-carbon
compound. In photorespiration, rubisco
adds O2 instead of CO2 in the Calvin cycle. Photorespiration eats up O2 and
organic fuel and releases CO2 without producing ATP or sugar. Photorespiration
can evolve relic because rubisco first evolved at a time when the atmosphere
had far less O2 and more CO2.