Explain how the world would be different if C4 plants and CAM plants had not evolved.
Since this is not my area of expertise, I searched Google under the key words "C4 CAM plants" to get these possible sources:
http://wc.pima.edu/~bfiero/tucsonecology/plants/plants_photosynthesis.htm
http://www.biologie.uni-hamburg.de/b-online/e24/24b.htm
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/C4plants.html
http://en.wikipedia.org/wiki/C4_carbon_fixation
(Broken Link Removed)
You can use the information from these and other sources listed to give your explanation. In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.
I hope this helps. Thanks for asking.
To understand how the world would be different if C4 plants and CAM plants had not evolved, let's start by explaining what C4 and CAM plants are and the advantages they provide.
1. C4 plants:
C4 plants are a type of plant that have adapted a unique pathway for photosynthesis, which allows them to thrive in hot and dry environments. They have higher water and nitrogen use efficiency compared to other plants. They concentrate carbon dioxide (CO2) around the enzyme responsible for capturing it, reducing the loss of water through open stomata.
2. CAM plants:
CAM (Crassulacean Acid Metabolism) plants are another category of plants that have evolved a special adaptation to survive in arid conditions. They open their stomata at night and store CO2 as organic acids, which are converted back to CO2 during the day for photosynthesis. This helps minimize water loss by reducing the amount of time stomata need to be open.
If C4 and CAM plants had not evolved, the world would experience several significant differences:
1. Changes in ecosystem structure:
C4 and CAM plants play crucial roles in many ecosystems. C4 plants are dominant in grasslands and savannas, while CAM plants are prevalent in arid environments such as deserts. Without these adaptations, the vegetation types in these areas would be different, likely consisting of plants that are less efficient in water and nutrient use.
2. Decreased agricultural productivity:
C4 plants, including many important crops like maize, sugarcane, and sorghum, have higher productivity in hot climates and low water availability. If C4 plants had not evolved, these crops would not have been able to grow efficiently in those environments. The absence of CAM plants would also reduce agricultural options in dry regions.
3. Increased water usage:
C4 and CAM plants have evolved mechanisms to minimize water loss. Without them, more plants would rely on the traditional C3 photosynthesis pathway. C3 plants generally have higher rates of transpiration, leading to increased water usage. This could exacerbate water scarcity issues in regions already struggling with limited water resources.
4. Altered carbon cycling and climate change:
C4 plants are more efficient at fixing and storing carbon than C3 plants. Therefore, the absence of C4 plants would likely result in altered carbon cycling patterns, potentially leading to increased atmospheric CO2 levels. This could exacerbate climate change by contributing to the greenhouse effect.
In conclusion, if C4 and CAM plants had not evolved, the world would experience changes in ecosystem structure, decreased agricultural productivity in certain regions, increased water usage, and potentially more significant climate change impacts. The evolution of these plants has enabled them to successfully adapt to and thrive in specific environmental conditions, making them vital components of our planet's ecosystems.