Solution: The above structure is of a chloroplast which is present in plant cells. (a) This structure can be observed in the cell of a plant. (b) Since chloroplast can self-replicate, it can be...
Examine the figure
Complete the flow chart for cyclic photophosphorylation of the photosystem-I
Solution:
Observe the diagram and answer the following.
a. Which group of plants exhibits these two types of cells?
b. What is the first product of the C4 cycle?
c. Which enzyme is there in bundle sheath cells and mesophyll cells?
Solution: (a) Bundle sheath cells and mesophyll cells are characteristics of monocot plants. (b) Oxaloacectic acid (OAA) is the first stable compound produced in the C4 cycle. (c) PEP carboxylase,...
What can we conclude from the statement that the action and absorption spectrum of photosynthesis overlap? At which wavelength do they show peaks?
Solution: To comprehend this, we must examine the graphs below. The first graph depicts the rate of photosynthesis as determined by oxygen release. The absorption of different wavelengths of light...
In the diagram given below what is label A, B and C. What type of phosphorylation is possible in this?
Solution: It's feasible to do cyclic photophosphorylation here. The creation of ATP from ADP and inorganic phosphate in the presence of light is known as photophosphorylation.
Why photorespiration does not take place in C4 plants?
Solution: C4 plants do not experience photorespiration because they use a method to raise the concentration of carbon dioxide at the enzyme site. When the C4 acid from the mesophyll is broken down...
Why is Rubisco enzyme the most abundant enzyme in the world?
Solution: During the Calvin cycle, the enzyme catalyzes the conversion of carbon dioxide to sugar. Rubisco can be found everywhere, from cyanobacteria to the undersides of enormous trees. Rubisco...
Name the two important enzymes of the C4 pathway, and explain their role in fixing CO2?
Solution: RuBisCO and PEPcase are two key enzymes in the C3 and C4 pathways, respectively. In C3 plants, RuBisCO is the predominant carbon dioxide acceptor, whereas, in C4 plants, PEPcase is the...
What special anatomical features are displayed by leaves of C4 plants? How do they provide an advantage over the structure of C3 plants?
Solution: A coating of giant cells surrounds the vascular bundles in leaves. Chloroplast, in particular, impregnates multiple layers of cells surrounding the bundle cell. Gases cannot pass through...
Why is the Rubisco enzyme more appropriately called RUBP Carboxylase-Oxygenase and what important role does it play in photosynthesis?
Solution: The RuBisCO enzyme is attracted to both carbon dioxide and oxygen. This binding, however, is a competitor. It has a stronger affinity for carbon dioxide than it does for oxygen. The...
List the important events and end products of the light reaction?
Solution: The following are important events and end products of the light reaction. It's crucial to note that these events are listed in the order in which scientists discovered them, not in the...
In the figure given below, the lighter line (upper) indicates the action spectrum for photosynthesis and the black line (lower) indicates the absorption spectrum of chlorophyll a. Answer the following
a. What does the action spectrum indicate? How can we plot an action spectrum?
b. How can we derive an absorption spectrum for any substance?
Solution: a. The photosynthetic rate is indicated by the action spectrum. The measurement is oxygen release, which can be compared to the action spectrum by looking at the oxygen releases on the...
Under what conditions are C4 plants superior to C3?
Solution: Under the following conditions, C4 plants outperform C3 plants: Even at low CO2 concentrations, C4 plants can perform photosynthesis. Saturation occurs in C4 plants around 360 l L1, but...
Which property of the pigment is responsible for its ability to initiate the process of photosynthesis? Why is the rate of photosynthesis higher in the red and blue regions of the spectrum of light?
Solution: Chlorophyll a is the most abundant pigment in plants. The optimal efficiency between blue and red light wavelengths is demonstrated by this pigment. Because pigments can absorb light of a...
Is it correct to say that photosynthesis occurs only in leaves of a plant? Besides leaves, what are the other parts that may be capable of carrying out photosynthesis? Justify.
Solution: Photosynthesize can occur in any portion of the plant that is green in color. As a result, the assertion is incorrect. Chlorophyll roots from Trap and Timisoara, as well as photosynthesis,...
Suppose Euphorbia and Maize are grown in the tropical area.
a. Which one of them do you think will be able to survive under such conditions?
b. Which one of them is more efficient in terms of photosynthetic activity?
c. What difference do you think are there in their leaf anatomy?
Solution: a. Maize is a C4 plant, while euphorbia is a CAM plant. Both are capable of surviving in tropical climates. b. Maize is a C4 plant, which means it has higher photosynthetic efficiency. c....
A cyclic process is occurring in a C3 plant, which is light-dependent and needs O2. This process doesn’t produce energy rather it consumes energy.
a. Can you name the given process?
b. Is it essential for survival?
c. What are the end products of this process?
d. Where does it occur?
Solution: (a) Photorespiration, is a process that occurs in chloroplasts, mitochondria, and peroxisomes. (b) Photorespiration happens when there is an abundance of oxygen rather than carbon dioxide,...
Why do we believe chloroplast and mitochondria to be semi-autonomous organelle?
Solution: Because chloroplasts have their own DNA, they are referred to as semi-autonomous organelles. Furthermore, they have the ability to create their own energy and do not require the cell....
Tomatoes, carrots and chillies are red due to the presence of one pigment. Name the pigment. Is it a photosynthetic pigment?
Solution: The pigment Lycopene is responsible for the red color of tomatoes, carrots, and chilies. This isn't a pigment that helps with photosynthesis. The plastid which contains this pigment is...
In a way, green plants and cyanobacteria have synthesized all the food on the earth. Comment.
Solution: To a large extent, this is correct, as cyanobacteria and green plants have created all of the food on the planet. Other autotrophs exist, although their contribution to the food chain of...
The entire process of photosynthesis consists of a number of reactions. Where in the cell does each of these take place?
a. Synthesis of ATP & NADPH __________________________
b. Photolysis of water __________________________
c. Fixation of CO2 __________________________
d. Synthesis of sugar molecule __________________________
e. Synthesis of starch __________________________
Solution: (a) occurs in the outer side of the thylakoid membrane (b) is conducted on the inner side of the thylakoid membrane (c) is performed in the stroma of the chloroplast (d) takes place in the...
Is it correct to say that photosynthesis occurs only in leaves of a plant? Besides leaves, what are the other parts that may be capable of carrying out photosynthesis? Justify.
Solution: Photosynthesize can occur in any portion of the plant that is green in color. As a result, the assertion is incorrect. Chlorophyll roots from Trap and Timisoara, as well as photosynthesis,...
Suppose Euphorbia and Maize are grown in the tropical area.
a. Which one of them do you think will be able to survive under such conditions?
b. Which one of them is more efficient in terms of photosynthetic activity?
c. What difference do you think are there in their leaf anatomy?
Solution: a. Maize is a C4 plant, while euphorbia is a CAM plant. Both are capable of surviving in tropical climates. b. Maize is a C4 plant, which means it has higher photosynthetic efficiency. c....
A cyclic process is occurring in a C3 plant, which is light-dependent and needs O2. This process doesn’t produce energy rather it consumes energy.
a. Can you name the given process?
b. Is it essential for survival?
c. What are the end products of this process?
d. Where does it occur?
Solution: (a) Photorespiration, is a process that occurs in chloroplasts, mitochondria, and peroxisomes. (b) Photorespiration happens when there is an abundance of oxygen rather than carbon dioxide,...
Why do we believe chloroplast and mitochondria to be semi-autonomous organelle?
Solution: Because chloroplasts have their own DNA, they are referred to as semi-autonomous organelles. Furthermore, they have the ability to create their own energy and do not require the cell....
Tomatoes, carrots and chillies are red due to the presence of one pigment. Name the pigment. Is it a photosynthetic pigment?
Solution: The pigment Lycopene is responsible for the red color of tomatoes, carrots, and chilies. This isn't a pigment that helps with photosynthesis. The plastid which contains this pigment is...
In a way, green plants and cyanobacteria have synthesized all the food on the earth. Comment.
Solution: To a large extent, this is correct, as cyanobacteria and green plants have created all of the food on the planet. Other autotrophs exist, although their contribution to the food chain of...
In what kind of plants do you come across ‘Kranz’ anatomy? To which conditions are those plants better adapted? How are these plants better adapted than the plants which lack this anatomy?
Solution: C4 plants, such as maize, sugarcane, and others, have Kranz anatomy. These plants can withstand extremes in temperature and light intensity. These plants have also evolved to thrive in...
Six turns of the Calvin cycle are required to generate one mole of glucose. Explain.
Solution: For one molecule of carbon dioxide to be reduced, two molecules of ATP and two molecules of NADPH are required during the Calvin cycle. Because glucose is a 6-carbon chemical, 6 carbon...
Find out how Melvin Calvin worked out the complete biosynthetic pathway for synthesis of sugar.
Solution: Experiments at the University of California led to the discovery of the full pathway for sugar synthesis by Melvin Calvin and his colleagues. They took the following steps to do this: The...
Explain how during light reaction of photosynthesis, ATP synthesis is a chemiosmotic phenomenon.
Solution: Chemiosmotic movement is the movement of ions through a semi-permeable membrane and down an electron gradient. During the light reaction of photosynthesis, ions pass over the thylakoid...
Why does the rate of photosynthesis decrease at higher temperatures?
Solution: Photosynthesis is a process that is aided by enzymes. We know that enzymes perform best in a specific temperature range. An enzyme cannot function when the temperature exceeds this range....
What conditions enable Rubisco to function as an oxygenase? Explain the ensuing process.
Solution: Rubisco has an affinity with carbon dioxide as well as oxygen. The binding of Rubisco with either of them, however, is competitive. This means that if the $C{{O}_{2}}$ concentration is...
In tropical rain forests, the canopy is thick and plants growing below receive filtered light. How are they able to carry out photosynthesis?
Solution: We know that light is rarely a limiting factor for photosynthesis because light saturation can be achieved with just 10% of full sunlight. Less light may limit the rate of photosynthesis...
Photosynthetic organisms occur at different depths in the ocean. Do they receive qualitatively and quantitatively the same light? How do they adapt to carry out photosynthesis under these conditions?
Solution: They do not receive the same amount of light in terms of both quality and quantity. The importance of solar radiation in living cannot be overstated. The photosynthetic pigments of these...
If a green plant is kept in dark with proper ventilation, can this plant carry out photosynthesis? Can anything be given as a supplement to maintain its growth or survival?
Solution: Carbon dioxide is still present when a plant is kept in the dark and properly ventilated. A sufficient amount of water can be provided to the plant to ensure its life. The seed, however,...
How are photosynthesis and respiration related to each other?
Solution: Photosynthesis produces glucose, which is needed in cellular respiration to produce ATP. After that, the glucose is converted to carbon dioxide, which is subsequently used in...
Do reactions of photosynthesis called, as ‘Dark Reaction’ needs light? Explain.
Solution: The biosynthetic phase of photosynthesis, during which carbohydrate synthesis occurs, is known as the Dark Reaction. This portion of photosynthesis is known as Dark Reaction because it is...
Chlorophyll ‘a’ is the primary pigment for a light reaction. What are accessory pigments? What is their role in photosynthesis?
Solution: Accessory pigments are pigments that aid chlorophyll in capturing solar light. They are known to support chlorophyll in the trapping of solar radiation. Accessory pigments aid in the...
Succulents are known to keep their stomata closed during the day to check transpiration. How do they meet their photosynthetic CO2 requirements?
Solution: During the day, succulent plants keep their stomata closed. This, however, limits the amount of carbon dioxide that can enter the system. Succulent plants have developed a particular way...
What is the basis for designating C3 and C4 pathways of photosynthesis?
Solution: Carbon dioxide and water mix during the biosynthetic phase to form carbohydrates or sugar molecules. Carbon fixation is the name given to this carbon dioxide reaction. Carbon fixation...
Which products formed during the light reaction of photosynthesis are used to drive the dark reaction?
Solution: The major photosynthetic pigment chlorophyll a, as well as accessory pigments such as chlorophyll b, chlorophyll c, and carotenoids, trap sunlight to carry out photosynthesis' light...
ATPase enzyme consists of two parts. What are those parts? How are they arranged in the thylakoid membrane? Conformational change occurs in which part of the enzyme?
Solution: The ATPase enzyme is made up of two parts: A part called FO is implanted in the membrane and produces a transmembrane channel that allows protons to diffuse across the membrane more...
Where is NADP reductase enzyme located in the chloroplast? What is the role of this enzyme in proton gradient development?
Solution: NADP reductase is an enzyme that aids in the decrease of a molecule's oxidative state... It comes in two varieties- NADP and NADPH. When a molecule is oxidized, NADP absorbs an electron...
Some of these terms/chemicals are associated with the C4 cycle. Explain.
a. Hatch slack pathway
b. Calvin cycle
c. PEP carboxylase
d. Bundle sheath cells
Solution: Hatch slack pathway- In C4 plants the process is called the Hatch & Slack Pathway, the glucose synthesis process. The Calvin Cycle is followed by every photosynthetic plant, although...
Does moonlight support photosynthesis?
Solution: A photon is adsorbed by Photosystem II in photosynthesis to break down water into oxygen and protons in solution. The photosystem must absorb yet another photon to fuel the Calvin cycle's...
Analyse the above reaction and answer the following questions:
a. How many molecules of ATP & NADPH are required to fix one molecule of CO2?
b. Where in the chloroplast does this process occur?
Solution: The above reaction is of reduction of glucose to carbohydrates which occurs in the stroma of the chloroplast where the Dark reaction takes place. So, the following are the answers to the...
Can girdling experiments be done in monocots? If yes, how? If no, why not?
Solution: Girdling is the process of removing the tree's bark in the form of a ring. The xylem is kept intact in this case so that it can feed minerals and water to the tree's various components....
a. NADP reductase enzyme is located on _________________.
b. Breakdown of proton gradient leads to release of _________________.
Solution: The NADP reductase enzyme is found on the stroma side of the grana thylakoids. The stacks of thylakoids are known as grana. The figure depicts a single thylakoid, which indicates the...
Cyanobacteria and some other photosynthetic bacteria don’t have chloroplasts. How do they conduct photosynthesis?
Solution: In plants and algae, the photosynthetic process takes place in microscopic organelles called chloroplasts, which are found inside cells. Light-harvesting pigments in more basic...
2H2O 4H+ + O2 + 4e–
Based on the above equation, answer the following questions:
a. Where does this reaction take place in plants?
b. What is the significance of this reaction?
Solution: The above reaction shows Photolysis and the following questions have been answered. It happens in PS II, which is a water molecule decomposition reaction.Water splitting (photolysis which...
When is added to PEP, the first stable product synthesised is:
a. Pyruvate
b. Glyceraldehyde-3-phosphate
c. Phosphoglycerate
d. Oxaloacetate
Solution: In C 4 plants, mesophyll cells are responsible for the early fixation of Carbon dioxide or carboxylation. PEP carboxylase (or PEP case) is a Carbon dioxide fixation enzyme found in the...
The reaction that is responsible for the primary fixation of is catalysed by
a. RuBP carboxylase
b. PEP carboxylase
c. RuBP carboxylase and PEP carboxylase
d. PGA synthase
Solution: Carboxylation is the reaction that causes carbon dioxide to be fixed in the first place. The RuBP carboxylase catalyzes this process, which results in the formation of two molecules of...
The enzyme that is not found in a C3 plant is
a. RuBP Carboxylase
b. PEP Carboxylase
c. NADP reductase
d. ATP synthase
Solution: The Phospho Enol Pyruvate (PEP) carboxylase is found in the mesophyll cells of C 4 plants and catalyzes the conversion of PEP to oxaloacetate. (OAA) is the first 4C stable chemical...
The correct sequence of flow of electrons in the light reaction is
a. PSII, plastoquinone, cytochromes, PSI, ferredoxin
b. PSI, plastoquinone, cytochromes, PSII, ferredoxin
c. PSI, ferredoxin, PSII,
d. PSI, plastoquinone, cytochromes, PSII, ferredoxin
Solution: Inside thylakoids, light processes take place. It is dependent on the presence of light. It involves water photolysis (the splitting of water into H 2 and O 2 and the generation of...
Splitting of water is associated with
a. Photosystem I
b. The lumen of thylakoid
c. Both Photosystem I and II
d. The inner surface of the thylakoid membrane
Solution: Photosystem II is involved in the splitting up of water or photolysis, and it is exclusively found in the membrane of thylakoids. So, the correct answer is (d).
PEP is the primary CO2 acceptor in
a. C4 plants
b. C3 plants
c. C2 plants
d. Both C3 and C4 plants
Solution: Phosphoenol Pyruvate (PEP) is located in the mesophyll cell of C4 plants, where it takes ambient CO2 and transforms it into the oxaloacetate molecule. To cope with photorespiratory losses,...
The dark reaction in photosynthesis is called so because of
a. It can occur in dark also
b. It does not depend on light energy
c. It cannot occur during daylight
d. It occurs more rapidly at night
Solution: Light isn't required for dark reactions. Dark reaction, on the other hand, generates energy molecules from ATP and NADPH. There is no need for a photosystem. Water does not undergo...
During light reaction in photosynthesis, the following are formed:
a. ATP and sugar
b. Hydrogen, O2 and sugar
c. ATP, hydrogen and O2
d. ATP, hydrogen and O2 donor
Solution: Inside thylakoids, light reactions take place. It is dependent on the presence of light. It involves water photolysis (the splitting of water into H 2 and O 2 and the generation of...
The energy required for ATP synthesis in PSII comes from
a. Proton gradient
b. Electron gradient
c. Reduction of glucose
d. Oxidation of glucose
Solution: \[2{{H}_{2}}O\to 4{{H}^{+}}+{{O}_{2}}+4{{e}^{-}}\] Since this reaction occurs on the inner side of the thylakoid membrane, the protons produced are trapped in the thylakoid lumen. Protons...
Chemosynthetic bacteria obtain energy from
a. Sun
b. Infrared rays
c. Organic substances
d. Inorganic chemicals
Solution: Chemosynthetic bacteria are organisms that use inorganic chemicals as a source of energy and convert them to organic compounds. They get their energy through the oxidation of inorganic...
Which light range is least effective in photosynthesis?
a. Blue
b. Green
c. Red
d. Violet
Solution: Photosynthesis is most efficient in the blue and red light spectrums. The energy carried by blue wavelengths of light is greater than that carried by red wavelengths. As a result, the most...
Which range of wavelength (in nm) is called photosynthetically active radiation (PAR)?
a. 100 – 390
b. 390 – 430
c. 400 – 700
d. 760 – 100,00
Solution: The wavelength of sunlight or solar energy that reaches the earth ranges from 300 nm (in the ultra-violet range) to 2600 nm (in the infra-red range). Photo synthetically active radiation...
Which pigment acts directly to convert light energy to chemical energy?
a. Chlorophyll a
b. Chlorophyll b
c. Xanthophyll
d. Carotenoid
Solution: Since it is found in all photosynthetic plants except bacteria, chlorophyll an is known as the universal photosynthetic pigment. As it performs the primary photosynthesis process, which...
Which metal ion is a constituent of chlorophyll?
a. Iron
b. Copper
c. Magnesium
d. Zinc
Solution: Chlorophyll contains magnesium as a component. Green photosynthetic pigments are called chlorophyll. The chloroplasts of higher plants have five forms of chlorophyll: a, b, c, d, and e....