In the case of water loss, the plant can perform two alternative photosynthesis pathways. Mention the name of these two pathways.
Answers
Answer:
Explanation:
RuBP oxygenase-carboxylase (rubisco), a key enzyme in photosynthesis, is the molecular equivalent of a good friend with a bad habit. In the process of carbon fixation, rubisco incorporates carbon dioxide (\text{CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript) into an organic molecule during the first stage of the Calvin cycle. Rubisco is so important to plants that it makes up 30\%30%30, percent or more of the soluble protein in a typical plant leaf^1
1
start superscript, 1, end superscript. But rubisco also has a major flaw: instead of always using \text{CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript as a substrate, it sometimes picks up \text O_2O
2
start text, O, end text, start subscript, 2, end subscript instead.
This side reaction initiates a pathway called photorespiration, which, rather than fixing carbon, actually leads to the loss of already-fixed carbon as \text{CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript. Photorespiration wastes energy and decreases sugar synthesis, so when rubisco initiates this pathway, it's committing a serious molecular faux pas.
In this article, we'll explore why photorespiration happens, when it's most likely to take place (hint: think hot and dry conditions), and how it actually works.
Rubisco binds to either \text{CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript or \text O_2O
2
start text, O, end text, start subscript, 2, end subscript
As we saw in the introduction, the enzyme rubisco can use either \text {CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript or \text O_2O
2
start text, O, end text, start subscript, 2, end subscript as a substrate. Rubisco adds whichever molecule it binds to a five-carbon compound called ribulose-1,5-bisphosphate (RuBP). The reaction that uses \text {CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript is the first step of the Calvin cycle and leads to the production of sugar. The reaction that uses \text O_2O
2
start text, O, end text, start subscript, 2, end subscript is the first step of the photorespiration pathway, which wastes energy and "undoes" the work of the Calvin cycle^2
2
squared.
Answer:
Osmotic pressure and Diffusion.
Explanation:
hope it will helpful for you!