238164
Three major ways in which different cells handle pyruvic acid are as follows, except -
1 Lactic acid fermentation
2 Photorespiration
3 Aerobic respiration
4 Alcoholic fermentation
Explanation:
B There are 3 major ways in which different cells handle pyruvic acid produced by glycolysis, there are, anaerobic respiration including lactic acid fermentation, alcoholic fermentation \& aerobic respiration. Lactic acid fermentation- Pyruvic acid $+\mathrm{NADH} \rightarrow$ Lactic acid $+\mathrm{NAD}^{+}$ Aerobic respiration (in glycolysis) Glucose $\rightarrow$ Pyruvic acid +2 ATP Alcoholic fermentation- $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \rightarrow 2 \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}+2 \mathrm{CO}_{2}$ Glucose $\rightarrow 2$ pyruvate $\rightarrow 2$ acetaldehyde $\rightarrow 2$ ethanol Photorespiration- Ribulose 1,5-biphosphate $+\mathrm{O}_{2} \underset{\text { oxygenase }}{\stackrel{\text { RuBP }}{\longrightarrow}}$ PGA + Phosphoglycolate $2 \mathrm{C}$
AP EAMCET-03.09.2021 Shift-I
Photosynthesis in higher plants
238165
Photorespiration RuBisCO binds with $\mathrm{O}_{2}$ to form (i) Phosphoglycerate (ii) Phosphoglycolate (iii) Glyceraldehyde-3-Phosphate (iv) Phosphoenol pyruvate The correct combination is :
1 (i) and (ii)
2 (ii) and (iii)
3 (iii) and (iv)
4 (i) and (iv)
Explanation:
A $\mathrm{RuBisCO}$ can bind to either carbondioxide or oxygen depending on environmental condition. Binding to carbondioxide and initiation of the calvinc cycles is favoured at low temperatures and at a high carbon dioxide-to-oxygen ratio in $\mathrm{RuBisCO}$, an oxygen molecule can bind comfortable in the site designed to bind to carbon dioxide. The RuBP binds with $\mathrm{O}_{2}$ to form one molecule of PGA ( $3 \mathrm{c}$ compound) and phosphoglycolate (2c compound) in the pathway of photorespiration. {rlrl} |Ribulose 1,5-biphosphate $+_{2}$ | $}{}$ | PGA | | |---|---|---|---| |$5 $ | | $3 $ | | + | Phosphoglycolate | | | $2 $
TS EAMCET-02.05.2018 Shift-II
Photosynthesis in higher plants
238166
In the given figure, what are the substances labelled as $P, Q, R$ and $S$ ?
B In the given diagram, it represents $\mathrm{C}_{2}$ cycle or photorespiration. The process has following steps:- - Oxygen bind with RuBP oxygenase and forms phosphoglycolate in chlroplast which gets converted to glycolate and is transported to peroxisome. - In peroxisomes it forms glyoxylate and then glycine. Glycine then enters the mitochondria, and looses $\mathrm{NH}_{4}$ and $\mathrm{CO}_{2}$ and forms serine. - The photo respiratory cycle with glycolate glyoxylate $\mathrm{CO}_{2}-$ serine are involved in this photorespiratory cycle. - Photorospiration occurs in chloroplast, peroxisome and mitochondria. It is wasteful process there is no formation of any product.
GUJCET-2017
Photosynthesis in higher plants
238162
Assertion (A) :Photorespiration is a wasteful process Reason (R) : There is no synthesis of sugars, ATP or NADPH, instead ATP is utilized and $\mathrm{CO}_{2}$ is released in photorespiration
1 Both $\mathrm{A}$ and $\mathrm{R}$ are correct $\mathrm{R}$ is the correct explanation of $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are correct, but $\mathrm{R}$ is not the correct explanation of $\mathrm{A}$
3 $\mathrm{A}$ is correct but $\mathrm{R}$ is incorrect
4 A is incorrect but R is correct
Explanation:
A Photorespiration is a process that occurs in plant when oxygen is present in high concentration. It is a wasteful process because it does not produce any sugars or ATP, and it actually consumes ATP. The wasteful nature of photorespiration has been puzzle to scientists for long time. While the exact reason is not confirmed but some hypothesis suggest that photorespiration help as a protective mechanism, preventing damage caused by excess oxygen in certain conditions. Another idea suggest that it regulate the temperature of plant.
AP EAPCET-23.05.2023
Photosynthesis in higher plants
238172
The first reaction in photorespiration
1 phosphorylation
2 decarboxylation
3 oxygenation
4 carboxylation
Explanation:
C Photorespiration is the uptake of $\mathrm{O}_{2}$ instead of $\mathrm{CO}_{2}$ in presence of light by green plants. The first reaction in photorespiration is oxygenation. In this step, $\mathrm{RuBP}$ is converted into one molecule of 3 PGA and one molecule of 2 phasphoglycolate. This reaction is catalysed by enzyme RuBisCO. $\underset{5 \mathrm{C}}{\text { Ribulose 1,5-biphosphate }+\mathrm{O}_{2}} \underset{\text { oxygenase }}{\stackrel{\mathrm{RuBP}}{\longrightarrow}} \underset{3 \mathrm{C}}{\mathrm{PGA}}$ + Phosphoglycolate $2 \mathrm{C}$
238164
Three major ways in which different cells handle pyruvic acid are as follows, except -
1 Lactic acid fermentation
2 Photorespiration
3 Aerobic respiration
4 Alcoholic fermentation
Explanation:
B There are 3 major ways in which different cells handle pyruvic acid produced by glycolysis, there are, anaerobic respiration including lactic acid fermentation, alcoholic fermentation \& aerobic respiration. Lactic acid fermentation- Pyruvic acid $+\mathrm{NADH} \rightarrow$ Lactic acid $+\mathrm{NAD}^{+}$ Aerobic respiration (in glycolysis) Glucose $\rightarrow$ Pyruvic acid +2 ATP Alcoholic fermentation- $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \rightarrow 2 \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}+2 \mathrm{CO}_{2}$ Glucose $\rightarrow 2$ pyruvate $\rightarrow 2$ acetaldehyde $\rightarrow 2$ ethanol Photorespiration- Ribulose 1,5-biphosphate $+\mathrm{O}_{2} \underset{\text { oxygenase }}{\stackrel{\text { RuBP }}{\longrightarrow}}$ PGA + Phosphoglycolate $2 \mathrm{C}$
AP EAMCET-03.09.2021 Shift-I
Photosynthesis in higher plants
238165
Photorespiration RuBisCO binds with $\mathrm{O}_{2}$ to form (i) Phosphoglycerate (ii) Phosphoglycolate (iii) Glyceraldehyde-3-Phosphate (iv) Phosphoenol pyruvate The correct combination is :
1 (i) and (ii)
2 (ii) and (iii)
3 (iii) and (iv)
4 (i) and (iv)
Explanation:
A $\mathrm{RuBisCO}$ can bind to either carbondioxide or oxygen depending on environmental condition. Binding to carbondioxide and initiation of the calvinc cycles is favoured at low temperatures and at a high carbon dioxide-to-oxygen ratio in $\mathrm{RuBisCO}$, an oxygen molecule can bind comfortable in the site designed to bind to carbon dioxide. The RuBP binds with $\mathrm{O}_{2}$ to form one molecule of PGA ( $3 \mathrm{c}$ compound) and phosphoglycolate (2c compound) in the pathway of photorespiration. {rlrl} |Ribulose 1,5-biphosphate $+_{2}$ | $}{}$ | PGA | | |---|---|---|---| |$5 $ | | $3 $ | | + | Phosphoglycolate | | | $2 $
TS EAMCET-02.05.2018 Shift-II
Photosynthesis in higher plants
238166
In the given figure, what are the substances labelled as $P, Q, R$ and $S$ ?
B In the given diagram, it represents $\mathrm{C}_{2}$ cycle or photorespiration. The process has following steps:- - Oxygen bind with RuBP oxygenase and forms phosphoglycolate in chlroplast which gets converted to glycolate and is transported to peroxisome. - In peroxisomes it forms glyoxylate and then glycine. Glycine then enters the mitochondria, and looses $\mathrm{NH}_{4}$ and $\mathrm{CO}_{2}$ and forms serine. - The photo respiratory cycle with glycolate glyoxylate $\mathrm{CO}_{2}-$ serine are involved in this photorespiratory cycle. - Photorospiration occurs in chloroplast, peroxisome and mitochondria. It is wasteful process there is no formation of any product.
GUJCET-2017
Photosynthesis in higher plants
238162
Assertion (A) :Photorespiration is a wasteful process Reason (R) : There is no synthesis of sugars, ATP or NADPH, instead ATP is utilized and $\mathrm{CO}_{2}$ is released in photorespiration
1 Both $\mathrm{A}$ and $\mathrm{R}$ are correct $\mathrm{R}$ is the correct explanation of $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are correct, but $\mathrm{R}$ is not the correct explanation of $\mathrm{A}$
3 $\mathrm{A}$ is correct but $\mathrm{R}$ is incorrect
4 A is incorrect but R is correct
Explanation:
A Photorespiration is a process that occurs in plant when oxygen is present in high concentration. It is a wasteful process because it does not produce any sugars or ATP, and it actually consumes ATP. The wasteful nature of photorespiration has been puzzle to scientists for long time. While the exact reason is not confirmed but some hypothesis suggest that photorespiration help as a protective mechanism, preventing damage caused by excess oxygen in certain conditions. Another idea suggest that it regulate the temperature of plant.
AP EAPCET-23.05.2023
Photosynthesis in higher plants
238172
The first reaction in photorespiration
1 phosphorylation
2 decarboxylation
3 oxygenation
4 carboxylation
Explanation:
C Photorespiration is the uptake of $\mathrm{O}_{2}$ instead of $\mathrm{CO}_{2}$ in presence of light by green plants. The first reaction in photorespiration is oxygenation. In this step, $\mathrm{RuBP}$ is converted into one molecule of 3 PGA and one molecule of 2 phasphoglycolate. This reaction is catalysed by enzyme RuBisCO. $\underset{5 \mathrm{C}}{\text { Ribulose 1,5-biphosphate }+\mathrm{O}_{2}} \underset{\text { oxygenase }}{\stackrel{\mathrm{RuBP}}{\longrightarrow}} \underset{3 \mathrm{C}}{\mathrm{PGA}}$ + Phosphoglycolate $2 \mathrm{C}$
238164
Three major ways in which different cells handle pyruvic acid are as follows, except -
1 Lactic acid fermentation
2 Photorespiration
3 Aerobic respiration
4 Alcoholic fermentation
Explanation:
B There are 3 major ways in which different cells handle pyruvic acid produced by glycolysis, there are, anaerobic respiration including lactic acid fermentation, alcoholic fermentation \& aerobic respiration. Lactic acid fermentation- Pyruvic acid $+\mathrm{NADH} \rightarrow$ Lactic acid $+\mathrm{NAD}^{+}$ Aerobic respiration (in glycolysis) Glucose $\rightarrow$ Pyruvic acid +2 ATP Alcoholic fermentation- $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \rightarrow 2 \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}+2 \mathrm{CO}_{2}$ Glucose $\rightarrow 2$ pyruvate $\rightarrow 2$ acetaldehyde $\rightarrow 2$ ethanol Photorespiration- Ribulose 1,5-biphosphate $+\mathrm{O}_{2} \underset{\text { oxygenase }}{\stackrel{\text { RuBP }}{\longrightarrow}}$ PGA + Phosphoglycolate $2 \mathrm{C}$
AP EAMCET-03.09.2021 Shift-I
Photosynthesis in higher plants
238165
Photorespiration RuBisCO binds with $\mathrm{O}_{2}$ to form (i) Phosphoglycerate (ii) Phosphoglycolate (iii) Glyceraldehyde-3-Phosphate (iv) Phosphoenol pyruvate The correct combination is :
1 (i) and (ii)
2 (ii) and (iii)
3 (iii) and (iv)
4 (i) and (iv)
Explanation:
A $\mathrm{RuBisCO}$ can bind to either carbondioxide or oxygen depending on environmental condition. Binding to carbondioxide and initiation of the calvinc cycles is favoured at low temperatures and at a high carbon dioxide-to-oxygen ratio in $\mathrm{RuBisCO}$, an oxygen molecule can bind comfortable in the site designed to bind to carbon dioxide. The RuBP binds with $\mathrm{O}_{2}$ to form one molecule of PGA ( $3 \mathrm{c}$ compound) and phosphoglycolate (2c compound) in the pathway of photorespiration. {rlrl} |Ribulose 1,5-biphosphate $+_{2}$ | $}{}$ | PGA | | |---|---|---|---| |$5 $ | | $3 $ | | + | Phosphoglycolate | | | $2 $
TS EAMCET-02.05.2018 Shift-II
Photosynthesis in higher plants
238166
In the given figure, what are the substances labelled as $P, Q, R$ and $S$ ?
B In the given diagram, it represents $\mathrm{C}_{2}$ cycle or photorespiration. The process has following steps:- - Oxygen bind with RuBP oxygenase and forms phosphoglycolate in chlroplast which gets converted to glycolate and is transported to peroxisome. - In peroxisomes it forms glyoxylate and then glycine. Glycine then enters the mitochondria, and looses $\mathrm{NH}_{4}$ and $\mathrm{CO}_{2}$ and forms serine. - The photo respiratory cycle with glycolate glyoxylate $\mathrm{CO}_{2}-$ serine are involved in this photorespiratory cycle. - Photorospiration occurs in chloroplast, peroxisome and mitochondria. It is wasteful process there is no formation of any product.
GUJCET-2017
Photosynthesis in higher plants
238162
Assertion (A) :Photorespiration is a wasteful process Reason (R) : There is no synthesis of sugars, ATP or NADPH, instead ATP is utilized and $\mathrm{CO}_{2}$ is released in photorespiration
1 Both $\mathrm{A}$ and $\mathrm{R}$ are correct $\mathrm{R}$ is the correct explanation of $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are correct, but $\mathrm{R}$ is not the correct explanation of $\mathrm{A}$
3 $\mathrm{A}$ is correct but $\mathrm{R}$ is incorrect
4 A is incorrect but R is correct
Explanation:
A Photorespiration is a process that occurs in plant when oxygen is present in high concentration. It is a wasteful process because it does not produce any sugars or ATP, and it actually consumes ATP. The wasteful nature of photorespiration has been puzzle to scientists for long time. While the exact reason is not confirmed but some hypothesis suggest that photorespiration help as a protective mechanism, preventing damage caused by excess oxygen in certain conditions. Another idea suggest that it regulate the temperature of plant.
AP EAPCET-23.05.2023
Photosynthesis in higher plants
238172
The first reaction in photorespiration
1 phosphorylation
2 decarboxylation
3 oxygenation
4 carboxylation
Explanation:
C Photorespiration is the uptake of $\mathrm{O}_{2}$ instead of $\mathrm{CO}_{2}$ in presence of light by green plants. The first reaction in photorespiration is oxygenation. In this step, $\mathrm{RuBP}$ is converted into one molecule of 3 PGA and one molecule of 2 phasphoglycolate. This reaction is catalysed by enzyme RuBisCO. $\underset{5 \mathrm{C}}{\text { Ribulose 1,5-biphosphate }+\mathrm{O}_{2}} \underset{\text { oxygenase }}{\stackrel{\mathrm{RuBP}}{\longrightarrow}} \underset{3 \mathrm{C}}{\mathrm{PGA}}$ + Phosphoglycolate $2 \mathrm{C}$
238164
Three major ways in which different cells handle pyruvic acid are as follows, except -
1 Lactic acid fermentation
2 Photorespiration
3 Aerobic respiration
4 Alcoholic fermentation
Explanation:
B There are 3 major ways in which different cells handle pyruvic acid produced by glycolysis, there are, anaerobic respiration including lactic acid fermentation, alcoholic fermentation \& aerobic respiration. Lactic acid fermentation- Pyruvic acid $+\mathrm{NADH} \rightarrow$ Lactic acid $+\mathrm{NAD}^{+}$ Aerobic respiration (in glycolysis) Glucose $\rightarrow$ Pyruvic acid +2 ATP Alcoholic fermentation- $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \rightarrow 2 \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}+2 \mathrm{CO}_{2}$ Glucose $\rightarrow 2$ pyruvate $\rightarrow 2$ acetaldehyde $\rightarrow 2$ ethanol Photorespiration- Ribulose 1,5-biphosphate $+\mathrm{O}_{2} \underset{\text { oxygenase }}{\stackrel{\text { RuBP }}{\longrightarrow}}$ PGA + Phosphoglycolate $2 \mathrm{C}$
AP EAMCET-03.09.2021 Shift-I
Photosynthesis in higher plants
238165
Photorespiration RuBisCO binds with $\mathrm{O}_{2}$ to form (i) Phosphoglycerate (ii) Phosphoglycolate (iii) Glyceraldehyde-3-Phosphate (iv) Phosphoenol pyruvate The correct combination is :
1 (i) and (ii)
2 (ii) and (iii)
3 (iii) and (iv)
4 (i) and (iv)
Explanation:
A $\mathrm{RuBisCO}$ can bind to either carbondioxide or oxygen depending on environmental condition. Binding to carbondioxide and initiation of the calvinc cycles is favoured at low temperatures and at a high carbon dioxide-to-oxygen ratio in $\mathrm{RuBisCO}$, an oxygen molecule can bind comfortable in the site designed to bind to carbon dioxide. The RuBP binds with $\mathrm{O}_{2}$ to form one molecule of PGA ( $3 \mathrm{c}$ compound) and phosphoglycolate (2c compound) in the pathway of photorespiration. {rlrl} |Ribulose 1,5-biphosphate $+_{2}$ | $}{}$ | PGA | | |---|---|---|---| |$5 $ | | $3 $ | | + | Phosphoglycolate | | | $2 $
TS EAMCET-02.05.2018 Shift-II
Photosynthesis in higher plants
238166
In the given figure, what are the substances labelled as $P, Q, R$ and $S$ ?
B In the given diagram, it represents $\mathrm{C}_{2}$ cycle or photorespiration. The process has following steps:- - Oxygen bind with RuBP oxygenase and forms phosphoglycolate in chlroplast which gets converted to glycolate and is transported to peroxisome. - In peroxisomes it forms glyoxylate and then glycine. Glycine then enters the mitochondria, and looses $\mathrm{NH}_{4}$ and $\mathrm{CO}_{2}$ and forms serine. - The photo respiratory cycle with glycolate glyoxylate $\mathrm{CO}_{2}-$ serine are involved in this photorespiratory cycle. - Photorospiration occurs in chloroplast, peroxisome and mitochondria. It is wasteful process there is no formation of any product.
GUJCET-2017
Photosynthesis in higher plants
238162
Assertion (A) :Photorespiration is a wasteful process Reason (R) : There is no synthesis of sugars, ATP or NADPH, instead ATP is utilized and $\mathrm{CO}_{2}$ is released in photorespiration
1 Both $\mathrm{A}$ and $\mathrm{R}$ are correct $\mathrm{R}$ is the correct explanation of $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are correct, but $\mathrm{R}$ is not the correct explanation of $\mathrm{A}$
3 $\mathrm{A}$ is correct but $\mathrm{R}$ is incorrect
4 A is incorrect but R is correct
Explanation:
A Photorespiration is a process that occurs in plant when oxygen is present in high concentration. It is a wasteful process because it does not produce any sugars or ATP, and it actually consumes ATP. The wasteful nature of photorespiration has been puzzle to scientists for long time. While the exact reason is not confirmed but some hypothesis suggest that photorespiration help as a protective mechanism, preventing damage caused by excess oxygen in certain conditions. Another idea suggest that it regulate the temperature of plant.
AP EAPCET-23.05.2023
Photosynthesis in higher plants
238172
The first reaction in photorespiration
1 phosphorylation
2 decarboxylation
3 oxygenation
4 carboxylation
Explanation:
C Photorespiration is the uptake of $\mathrm{O}_{2}$ instead of $\mathrm{CO}_{2}$ in presence of light by green plants. The first reaction in photorespiration is oxygenation. In this step, $\mathrm{RuBP}$ is converted into one molecule of 3 PGA and one molecule of 2 phasphoglycolate. This reaction is catalysed by enzyme RuBisCO. $\underset{5 \mathrm{C}}{\text { Ribulose 1,5-biphosphate }+\mathrm{O}_{2}} \underset{\text { oxygenase }}{\stackrel{\mathrm{RuBP}}{\longrightarrow}} \underset{3 \mathrm{C}}{\mathrm{PGA}}$ + Phosphoglycolate $2 \mathrm{C}$
238164
Three major ways in which different cells handle pyruvic acid are as follows, except -
1 Lactic acid fermentation
2 Photorespiration
3 Aerobic respiration
4 Alcoholic fermentation
Explanation:
B There are 3 major ways in which different cells handle pyruvic acid produced by glycolysis, there are, anaerobic respiration including lactic acid fermentation, alcoholic fermentation \& aerobic respiration. Lactic acid fermentation- Pyruvic acid $+\mathrm{NADH} \rightarrow$ Lactic acid $+\mathrm{NAD}^{+}$ Aerobic respiration (in glycolysis) Glucose $\rightarrow$ Pyruvic acid +2 ATP Alcoholic fermentation- $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \rightarrow 2 \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}+2 \mathrm{CO}_{2}$ Glucose $\rightarrow 2$ pyruvate $\rightarrow 2$ acetaldehyde $\rightarrow 2$ ethanol Photorespiration- Ribulose 1,5-biphosphate $+\mathrm{O}_{2} \underset{\text { oxygenase }}{\stackrel{\text { RuBP }}{\longrightarrow}}$ PGA + Phosphoglycolate $2 \mathrm{C}$
AP EAMCET-03.09.2021 Shift-I
Photosynthesis in higher plants
238165
Photorespiration RuBisCO binds with $\mathrm{O}_{2}$ to form (i) Phosphoglycerate (ii) Phosphoglycolate (iii) Glyceraldehyde-3-Phosphate (iv) Phosphoenol pyruvate The correct combination is :
1 (i) and (ii)
2 (ii) and (iii)
3 (iii) and (iv)
4 (i) and (iv)
Explanation:
A $\mathrm{RuBisCO}$ can bind to either carbondioxide or oxygen depending on environmental condition. Binding to carbondioxide and initiation of the calvinc cycles is favoured at low temperatures and at a high carbon dioxide-to-oxygen ratio in $\mathrm{RuBisCO}$, an oxygen molecule can bind comfortable in the site designed to bind to carbon dioxide. The RuBP binds with $\mathrm{O}_{2}$ to form one molecule of PGA ( $3 \mathrm{c}$ compound) and phosphoglycolate (2c compound) in the pathway of photorespiration. {rlrl} |Ribulose 1,5-biphosphate $+_{2}$ | $}{}$ | PGA | | |---|---|---|---| |$5 $ | | $3 $ | | + | Phosphoglycolate | | | $2 $
TS EAMCET-02.05.2018 Shift-II
Photosynthesis in higher plants
238166
In the given figure, what are the substances labelled as $P, Q, R$ and $S$ ?
B In the given diagram, it represents $\mathrm{C}_{2}$ cycle or photorespiration. The process has following steps:- - Oxygen bind with RuBP oxygenase and forms phosphoglycolate in chlroplast which gets converted to glycolate and is transported to peroxisome. - In peroxisomes it forms glyoxylate and then glycine. Glycine then enters the mitochondria, and looses $\mathrm{NH}_{4}$ and $\mathrm{CO}_{2}$ and forms serine. - The photo respiratory cycle with glycolate glyoxylate $\mathrm{CO}_{2}-$ serine are involved in this photorespiratory cycle. - Photorospiration occurs in chloroplast, peroxisome and mitochondria. It is wasteful process there is no formation of any product.
GUJCET-2017
Photosynthesis in higher plants
238162
Assertion (A) :Photorespiration is a wasteful process Reason (R) : There is no synthesis of sugars, ATP or NADPH, instead ATP is utilized and $\mathrm{CO}_{2}$ is released in photorespiration
1 Both $\mathrm{A}$ and $\mathrm{R}$ are correct $\mathrm{R}$ is the correct explanation of $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are correct, but $\mathrm{R}$ is not the correct explanation of $\mathrm{A}$
3 $\mathrm{A}$ is correct but $\mathrm{R}$ is incorrect
4 A is incorrect but R is correct
Explanation:
A Photorespiration is a process that occurs in plant when oxygen is present in high concentration. It is a wasteful process because it does not produce any sugars or ATP, and it actually consumes ATP. The wasteful nature of photorespiration has been puzzle to scientists for long time. While the exact reason is not confirmed but some hypothesis suggest that photorespiration help as a protective mechanism, preventing damage caused by excess oxygen in certain conditions. Another idea suggest that it regulate the temperature of plant.
AP EAPCET-23.05.2023
Photosynthesis in higher plants
238172
The first reaction in photorespiration
1 phosphorylation
2 decarboxylation
3 oxygenation
4 carboxylation
Explanation:
C Photorespiration is the uptake of $\mathrm{O}_{2}$ instead of $\mathrm{CO}_{2}$ in presence of light by green plants. The first reaction in photorespiration is oxygenation. In this step, $\mathrm{RuBP}$ is converted into one molecule of 3 PGA and one molecule of 2 phasphoglycolate. This reaction is catalysed by enzyme RuBisCO. $\underset{5 \mathrm{C}}{\text { Ribulose 1,5-biphosphate }+\mathrm{O}_{2}} \underset{\text { oxygenase }}{\stackrel{\mathrm{RuBP}}{\longrightarrow}} \underset{3 \mathrm{C}}{\mathrm{PGA}}$ + Phosphoglycolate $2 \mathrm{C}$
