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WorksheetsPhotorespiration, C4 & CAM pathway
Total questions: 30
Worksheet time: 16mins
Photorespiration occurs when ____ is used in the Calvin Cycle instead of Carbon Dioxide gas.
Water Vapor
Oxygen Gas
Nitrogen Gas
Hydrogen Ion
Plants that DO NOT have a way of 'preventing' Photorespiration are known as...
C3 Plants
C4 Plants
CAM Plants
C2 Plants
CAM and C4 Plants each prevent Photorespiration by...
Storing CO2 in a form that can be used during times their stomata are closed.
Keeping their stomata open at all times to prevent low CO2 levels.
A special carrier protein that prevents the entrance of Oxygen into leaves.
Altering (alosteric inhibition) the enzyme RUBISCO to prevent photorespiration.
C3 Plants are a higher risk of Photorespiration when....
It is hot and dry outside.
It is cool and damp outside.
It is hot and damp outside.
It is cool and dry outside.
CAM plants temporarily store CO2 in...
Malic Acid Molecules
Four Carbon Molecules
They don't they are at risk for Photorespiration.
Carboxylic Acid
Which plants take in CO2 at night and store it in vacuoles as 'malic acid'?
CAM Plants
C4 Plants
C3 Plants
C2 Plants
C3 Plants are called this because they produce...
3 Carbon PGA as part of the Calvin Cycle
3 Carbon Rubisco as part of the Calvin Cycle
3 Carbon Ribulose Bisphosphate as part of the Calvin Cycle
Why photorespiration occurs when the concentration of O2 is higher than the concentration CO2?
Rubisco has higher affinity to O2
Rubisco has higher affinity to CO2
CO2 act as competitive inhibitor
CO2 can bind to Rubisco
What is the product of photorespiration?
2 molecule of 3-Phosphoglycerate
Phosphoglycolate and 3-Phosphoglycerate
Glyceraldehyde-3-phosphate and Phosphoglycolate
2 molecule of Glyceraldehyde-3-phosphate
Describe the Kranz anatomy
Mesophyll cell arranged in ring form around bundle sheath cell
bundle sheath cell arranged in ring form around Mesophyll cell
Chlorophyll arranged in ring form around bundle sheath cell
Mesophyll cell arranged in ring form around epidermis
What is the first product of C4 pathway?
Oxaloacetate
Malate
3-Phosphoglycerate
Phosphoenolpyruvate
Why PEP Carboxylase is useful in C4 Pathway?
PEP carboxylase has no affinity to O2
PEP carboxylase has no affinity to CO2
PEP carboxylase function at high temperature
PEP carboxylase only bind to O2
What is the similarity between CAM pathway and C3 pathway?
Both occur in mesophyll cells
Both occur in bundle sheath cells
Both occur in during day time
Both occur in during night time
What is the similarity between C4 plant and CAM Pathway?
Both first product is Oxaloacetate
Carbon fixation occurred once in both
Both occurs in the same plant
Both first product is Malate
Why photorespiration is wasteful?
Phosphoglycolate breakdown into CO2 without producing organic molecule.
Phosphoglycolate is a high energy molecule
Photorespiration increase the production of Glyceraldehyde-3-phosphate by 40%
Which of the following is an example of CAM plant?
Sugar cane
Paddy
Cactus
Corn
In C4 plants, the Calvin cycle....
Takes place at night
Only occurs when the stomata are closed
Takes place in the mesophyll
Takes place in the bundle-sheath cells
What causes the high concentration of Oxygen in leaf during hot and dry day?
Stomata Closed
Photolysis of water
Carbon dioxide used in calvin cycle
Slow rate of photosynthesis
First carbon fixation in C4 pathway are catalyze by...
PEP Carboxylase
RuBP Carboxylase
Rubisco
Phosphofructokinase
CAM plant seperates carbon fixation
Spatially
Temporally
Mechanically
Chemically
Similarities between C4 pathway and CAM Pathway are
Both produce oxaloacetate as first product of carbon fixation
Both require Calvin cycles
Both produce 3-phosphoglycerate as first product of carbon fixation
Both occurs in the mesophyll cell
Oxaloacetate produce in CAM pathway are
reduced to malate and stored in vacuole
oxidize into PEP and stored in cytoplasm
reduce to malate and stored in the cytoplasm
Oxidized into PEP and stored in vacuole
Why malate is stored in vacuole in CAM plant?
To be decarboxylated during the day
To prevent decrease in pH in cytoplasm
To be decarboxylated during night
To be transported to bundle sheath cell
In C4 and CAM plants, carbon acceptors is/are _____________________ while fixation enzyme is/are _______________________.
RuBP ; rubisco
PEP ; PEP carboxylase
RuBP and PEP ; rubisco and PEP carboxylase
RuBP ; rubisco and PEP carboxylase
In C4 and CAM plants, which of the following is true if level of CO2 is low?
PEP carboxylase has low affinity towards CO2
PEP carboxylase has higher affinity towards O2
PEP carboxylase has high affinity towards both CO2 and O2
PEP carboxylase still has high affinity towards CO2
How does C4 pathway prevent photorespiration in C4 plants?
The pathway ensures availability of CO2 in bundle-sheath cell
It closes stomata to prevent CO2 escaping from the cell
It reduces concentration of O2 in bundle-sheath cell
It prevents closure of stomata
In cactus, the source of carbon dioxide for photosynthesis during the day is from ………………………
Malate
Pyruvate
Oxaloacetate
Atmospheric CO2
Which of the following reaction occurs in bundle sheath cell of C4 plants?
Malate is decarboxylated to form pyruvate
CO2 bind with PEP forming oxaloacetate
Oxaloacetate reduce to malate
Pyruvate is phosphorylated to form PEP
Which of following are example of C4 plants?
sugar cane
corn
pineapple
rice
The alternative pathways of photosynthesis using the C4 or CAM systems are said to be compromises. Why?
C4 compromises on water loss and CAM compromises on photorespiration.
Both minimize photorespiration but expend more ATP during carbon fixation.
CAM plants allow more water loss, whereas C4 plants allow less CO2 into the plant.
C4 plants allow less water loss but CAM plants allow more water loss.
