PLANT PHYSIOLOGY
PHOTOSYNTHESIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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lower levels of ozone in the atmosphere
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lower levels of nitrogen in the atmosphere
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higher levels of carbon dioxide and other greenhouse gases in the atmosphere
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higher levels of oxygen in the atmosphere
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Detailed explanation-1: -The Earth’s average surface temperature has increased by about 1.8°F (1.0°C) since the late 1800s. Human-caused greenhouse gas emissions are responsible for the observed warming.
Detailed explanation-2: -Global warming is the unusually rapid increase in Earth’s average surface temperature over the past century primarily due to the greenhouse gases released as people burn fossil fuels.
Detailed explanation-3: -Air temperatures on Earth have been rising since the Industrial Revolution. While natural variability plays some part, the preponderance of evidence indicates that human activities-particularly emissions of heat-trapping greenhouse gases-are mostly responsible for making our planet warmer.
Detailed explanation-4: -If the climate warms by another one degree Celsius, the atmosphere would be able to hold about 7% more water vapor. Most of that extra water vapor is going to come from the earth through increased evaporation and transpiration.
Detailed explanation-5: -Global average surface temperature has risen at an average rate of 0.17°F per decade since 1901 (see Figure 2), similar to the rate of warming within the contiguous 48 states.