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Photosynthesis.
Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.
Learning materials, instructional links.
Most life on Earth depends on photosynthesis .The process is carried out by plants, algae, and some types of bacteria, which capture energy from sunlight to produce oxygen (O 2 ) and chemical energy stored in glucose (a sugar). Herbivores then obtain this energy by eating plants, and carnivores obtain it by eating herbivores.
The process
During photosynthesis, plants take in carbon dioxide (CO 2 ) and water (H 2 O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose. The plant then releases the oxygen back into the air, and stores energy within the glucose molecules.
Chlorophyll
Inside the plant cell are small organelles called chloroplasts , which store the energy of sunlight. Within the thylakoid membranes of the chloroplast is a light-absorbing pigment called chlorophyll , which is responsible for giving the plant its green color. During photosynthesis , chlorophyll absorbs energy from blue- and red-light waves, and reflects green-light waves, making the plant appear green.
Light-dependent Reactions vs. Light-independent Reactions
While there are many steps behind the process of photosynthesis, it can be broken down into two major stages: light-dependent reactions and light-independent reactions. The light-dependent reaction takes place within the thylakoid membrane and requires a steady stream of sunlight, hence the name light- dependent reaction. The chlorophyll absorbs energy from the light waves, which is converted into chemical energy in the form of the molecules ATP and NADPH . The light-independent stage, also known as the Calvin cycle , takes place in the stroma , the space between the thylakoid membranes and the chloroplast membranes, and does not require light, hence the name light- independent reaction. During this stage, energy from the ATP and NADPH molecules is used to assemble carbohydrate molecules, like glucose, from carbon dioxide.
C3 and C4 Photosynthesis
Not all forms of photosynthesis are created equal, however. There are different types of photosynthesis, including C3 photosynthesis and C4 photosynthesis. C3 photosynthesis is used by the majority of plants. It involves producing a three-carbon compound called 3-phosphoglyceric acid during the Calvin Cycle, which goes on to become glucose. C4 photosynthesis, on the other hand, produces a four-carbon intermediate compound, which splits into carbon dioxide and a three-carbon compound during the Calvin Cycle. A benefit of C4 photosynthesis is that by producing higher levels of carbon, it allows plants to thrive in environments without much light or water. The National Geographic Society is making this content available under a Creative Commons CC-BY-NC-SA license . The License excludes the National Geographic Logo (meaning the words National Geographic + the Yellow Border Logo) and any images that are included as part of each content piece. For clarity the Logo and images may not be removed, altered, or changed in any way.
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Students are often asked to write an essay on Photosynthesis in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.
Let’s take a look…
What is photosynthesis.
Photosynthesis is how plants make their own food using sunlight. It happens in the leaves of plants. Tiny parts inside the leaves, called chloroplasts, use sunlight to turn water and carbon dioxide from the air into sugar and oxygen. The sugar is food for the plant.
The main things needed for photosynthesis are sunlight, water, and carbon dioxide. Roots soak up water from the soil. Leaves take in carbon dioxide from the air. Then, using sunlight, plants create food and release oxygen.
In the chloroplasts, sunlight energy is changed into chemical energy. This energy turns water and carbon dioxide into glucose, a type of sugar. Oxygen is made too, which goes into the air for us to breathe.
Photosynthesis is vital for life on Earth. It gives us food and oxygen. Without it, there would be no plants, and without plants, animals and people would not survive. It also helps take in carbon dioxide, which is good for the Earth.
Why is photosynthesis important.
This process is very important because it is the main way plants make food for themselves and for us, too. Without photosynthesis, plants could not grow, and without plants, animals and humans would not have oxygen to breathe or food to eat.
Photosynthesis happens in two main stages. In the first stage, the plant captures sunlight with its leaves. The sunlight gives the plant energy to split water inside its leaves into hydrogen and oxygen. The oxygen is released into the air, and the hydrogen is used in the next stage.
In the second stage, the plant mixes the hydrogen with carbon dioxide from the air to make glucose, which is a type of sugar that plants use for energy. This energy helps the plant to grow, make flowers, and produce seeds.
Photosynthesis is a key part of the cycle of life on Earth. By making food and oxygen, plants support life for all creatures. When animals eat plants, they get the energy from the plants, and when animals breathe, they use the oxygen that plants release. It’s a beautiful cycle that keeps the planet alive.
Photosynthesis is a process used by plants, algae, and some bacteria to turn sunlight, water, and carbon dioxide into food and oxygen. This happens in the green parts of plants, mainly the leaves. The green color comes from chlorophyll, a special substance in the leaves that captures sunlight.
The photosynthesis recipe.
When sunlight hits the leaves, the chlorophyll captures it and starts the food-making process. The energy from the sunlight turns water and carbon dioxide into glucose, a type of sugar that plants use for energy, and oxygen, which is released into the air. This process is like a recipe that plants follow to make their own food.
Photosynthesis is very important for life on Earth. It gives us oxygen, which we need to breathe. Plants use the glucose they make for growth and to build other important substances like cellulose, which they use to make their cell walls. Without photosynthesis, there would be no food for animals or people, and no oxygen to breathe.
Photosynthesis and the food chain.
All living things need energy to survive, and this energy usually comes from food. Plants are at the bottom of the food chain because they can make their own food using photosynthesis. Animals that eat plants get energy from the glucose in the plants. Then, animals that eat other animals get this energy too. So, photosynthesis is the start of the food chain that feeds almost every living thing on Earth.
Photosynthesis affects our lives in many ways. It gives us fruits, vegetables, and grains to eat. Trees and plants also give us wood, paper, and other materials. Plus, they provide shade and help make the air fresh and clean.
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In this essay we will discuss about Photosynthesis in Plants. After reading this essay you will learn about: 1. Meaning of Photosynthesis 2. Significance of Photosynthesis to Mankind 3. History 4. Photosynthetic Apparatus 5. Pigments 6. Quantum Requirement and Quantum Yield 7. Mechanism 8. Evidences for Existence of Light and Dark Reactions 9. Source of Oxygen 10. Factors Affecting.
Although literary meaning of photosynthesis is ‘synthesis with the help of light’ but this term is usually applied to a very important vital process by which the green plants synthesize organic matter in presence of light. Photosynthesis is sometimes called as carbon assimilation and is represented by the following traditional equation.
Chlorophylls and other photosynthetic pigments are found in the form of protein pigment complexes mainly in thylakoid membranes of grana. The latter are sites of primary photochemical reaction. Some of the protein-pigment complexes are also found in stroma lamellae.
Dark reaction of photosynthesis occurs in stroma. Besides necessary enzymes, some ribosomes and DNA have also been found in chloroplasts which give them (chloroplasts) a partial genetic autonomy.
Photosynthetic pigments are of three types:
(2) Carotenoids, and
(3) Phycobillins.
i. Chlorophylls and carotenoids are insoluble in water and can be extracted only with organic solvents.
ii. Phycobillins are soluble in water.
iii. Carotenoids include carotenes and xanthophylls. The latter are also called as carotenols.
iv. Different pigments absorb light of different wavelengths and characteristic absorption peak in vivo and in vitro.
v. They show property of fluoresces.
The distribution of the different types of photosynthetic pigments in plant kingdom is shown in table 11.1.
A new form of chlorophyll has been discovered recently by Chen et al (2010) from stromatolites of Shark Bay in Western Australia which they have called as chlorophyll f. This pigment is believed to absorb light upto 706 nm in vitro, with a fluorescence of 722 nm. (stromatolites are structures formed from layers of cyanobacteria (blue-green algae), and other microorganisms, calcium carbonate and sediments).
(1) Chlorophylls:
They are magnesium porphyrin compounds. The porphyrin ring consists of four pyrrol rings joined together by CH bridges. A long chain of C atoms called as phytol chain is attached to porphyrin ring at iv pyrrol ring.
I. Chemical structures of chlorophyll-a and chlorophyll-b are well established.
v. (In modern scientific literature, some plant physiologists equate PAR with visible part of spectrum of radiant energy which is erroneous. This is because such scientists working on photobiology use commercially available instruments that are limited to that portion of spectrum between 400-700 nm only, thus excluding visible light in the 700-760 and 390-400 nm range.)
vi. Only about 1% of the total solar energy received by the earth is absorbed by the pigments and is utilised in photosynthesis.
vii. There is very weak absorption by pigments in green part of the spectrum and hence, the chloroplasts appear green in green plants.
They chiefly absorb in the violet-blue and red parts of the spectrum. The absorption band shown by the chlorophylls in violet-blue region is also called as soret band. Characteristic absorption peaks shown by different chlorophylls both in vivo (i.e., intact cell) and in vitro (i.e., in solvents) are given in Table 11.2.
Absorption Spectra of Carotenoids:
These pigments absorb light energy in blue, blue- green and green parts of the spectrum.
Absorption Spectra of Phycobillins:
This can be explained further by a schematic model for the photo-oxidation of water given by Bessel Kok et al (1970) which is widely accepted and is called as S state mechanism or sometimes as water oxidizing clock. It consists of a series of 5 states called as S 0 , S 1 , S 2 , S 3 and S 4 which represent successively more oxidised forms of the water oxidizing system or oxygen evolving complex (OEC) S 0 is uncharged state.
Each short flash of light (photon or hv) converts S 0 to S 1 , S 1 to S 2 , S 2 to S 3 and S 3 to S 4 . After the S 4 state has acquired four positive charges, it gets four electrons back in one step oxidation of two molecules of H 2 O and returns back to S 0 with four fewer charges than S 4 (fig. 11.14).
However, the chemical nature of S state in this ‘clock’ is yet unknown. Once it was believed that P680 becomes oxidised by loss of one electron after a brief flash of light to P680 + but P680 cannot be S because it can lose only one electron and can accumulate only one positive charge.
Later studies have shown that various S states probably represent oxidation states of manganese including Mn 2+ , Mn 3+ and Mn 4+ . This hypothesis has received strong support from a variety of experiments, especially X-ray absorption and ESR studies which detect the manganese directly (Yano at al, 2006).
It is now known that the immediate electron donor to PSII is a tyrosine (an amino acid) residue which is often designated as Z or Y z in subunit D 1 of PSII reaction centre. (Y is code letter for tyrosine; hence Z is now called as Y z ). It is believed that tyrosine radical regains its electron by oxidizing a cluster of 4 Mn ions in OEC.
With each single electron transfer, the Mn cluster becomes more oxidized. Four single electron transfers (each corresponding with one photon (hv) of light) produce four positive charges on Mn cluster. In this state, Mn complex can take four electrons (4e-) from a pair of water molecules. The exact mechanism of photo-oxidation of H 2 O 2 however, remains elusive.
(The OEC is a 33kD complex situated on lumenal side of thylakoid. The 4H + released by photolysis of 2H 2 O molecules are released into lumen of thylakoid where they add to the proton gradient necessary for photophosphorylation. Apart from Mn 2+ and Cr ions, Ca 2+ ions are also believed to be essential for photolysis of water.)
(v) Electron Transport and the Production of Assimilatory Power (i.e., NADPH + H + + ATP):
It has already been said that when chlorophyll-a molecule receives a photon of light it becomes excited and expels the extra energy along with an electron in both the pigment systems. This electron after travelling through a number of electron carriers is either cycled back or is consumed in reducing NADP + (Nicotinamide Adenine Dinucleotide Phosphate) to NADPH + H + .
The extra light energy carried by the electron is utilised in the formation of ATP molecules at certain places during its transport. This process of the formation of ATP from ADP and inorganic phosphate (Pi) in photosynthesis is called as photosynthetic phosphorylation or photophosphorylation. Arnon has contributed a lot in our understanding of the electron transport and photophosphorylation in chloroplasts.
These are of two types:
(a) Non-cyclic Electron Transport and Non-cyclic Photophosphorylation (Z-Scheme):
This process of electron transport involves both PSI and PSII which act in tandem or series and is initiated by the absorption of a photon (quantum) of light by P700 form of chlorophyll- a molecule in pigment system I which gets excited. An electron is ejected from it so that an electron deficiency or a ‘hole’ is left in the P700 molecule (or in other words a positive charge comes on chlorophyll-a-molecule).
This ejected electron is trapped by FRS (Ferredoxin reducing substance) which is an unknown oxidation-reduction system with a redox potential (E 0 ‘) of -0.6 volts and may be a pteridene. The electron is now transferred to a non-heme iron protein called ferredoxin (Fd) with E’ 0 of-0.432 V. From ferredoxin the electron is transferred to NADP (E 0 ‘ = -0.32 V) via intermediate protein electron carrier ferredoxin-NADP reductase (FNR) so that NADP is reduced to NADPH + H + .
Most recent researches have shown that FRS is in-fact a series of electron carriers which in their reduced form are very unstable and difficult to be identified and are designated as A 0 A 1 Fe-S 1 ,Fe-S A & Fe-S B . A 0 is probably a chlorophyll molecule that receives electron from P700.
A 1 is believed to be phylloquinone (vit. K 1 ). Fe-S x , Fe-S A and Fe-S B are iron-sulphur centres situated on proteins in core complex I (CCI) and act as additional electron carriers. From Fe-S centres, the electron is transferred to ferredoxin (Fd) which is a small, water soluble iron-sulphur protein situated on stroma side of thylakoid membrane (Fig. 11.16).
Now, when a photon (quantum) of light is absorbed by P680 form of chlorophyll-a molecule in pigment system II, it gets excited and an electron is ejected from it so that an electron deficiency or a ‘hole’ is left behind in the P680 molecule. The ejected electron is trapped by a compound of unknown identity usually designated Y (Compound Y is sometimes called as Q because it also causes quenching of the characteristic fluorescence of chlorophyll-a in pigment system II).
This unknown compound forms oxidation-reduction system with a redox-potential (E 0 ‘) value more negative than 0.0 V. From Q the electron passes downhill along a series of compounds or intermediate electron carriers and is ultimately received by pigment system I where it ‘fills the hole.’ Redox potential of P700 in pigment system is + 0.43 V.
The series of compounds consists of (i) cytochrome b-559 (E 0 ‘ = + 0. 055 V), (ii) plastoquinone (PQ) whose chemical structure shows similarity with vitamins of K Series. It has a redox potential (E 0 ‘) of + 0.113 V, (iii) cytochrome ƒ (E 0 ‘ = + 0.36 V) and (iv) plastocyanin (PC) which is copper containing protein (E 0 ‘ = + 0.39 V).
At one place during the electron transport i.e., between plastoquinone and cytochrome ƒ there is enough change in free energy which allows phosphorylation of one molecule of ADP to form one ATP molecule (photophosphorylation).
Most recent researches have shown that from p680, the electron is transferred to unknown compound ‘Q’ via pheophytin. The latter is special form of chlorophyll-a which lacks magnesium atom (Fig. 11.2B). The unknown compound Q exists in two forms Q A & Q B .
It is now known that Q A and Q B are infact specialized plastoquinones (PQ) which receive electron from pheophytin and transfer it to Cyt. b 6 f complex. Q A is attached strongly to D 2 protein, while Q B is attached loosely to D 1 protein in core complex II (CC II). After the Q B has received two electrons from Q A (one by one in two turns), it also takes two protons (2H + ) from stroma and is fully reduced to uncharged plastoquinol or plastohydroquinone (PQH 2 or PQ B H 2 ).
The PQH 2 is now released from the reaction centre and is replaced by another molecule of PQ which now occupies the Q B site (11.16). From PQH 2 , electrons are transferred to cytochrome b 6 f complex and its two protons (2H + ) are expelled into the lumen of thylakoid. Finally, the electrons from Cyt b 6 f complex reach to PSI via plastocyanin (PC).
(It is important to note that Q A is one electron acceptor, while Q B is two electrons acceptor).
i. Cytochrome ƒ is a typical c type of cytochrome, ‘ ƒ ’ is abbreviated from ‘frons’ which in Latin means leaf).
The ‘hole’ in pigment system I has been filled by the electron coming from pigment system II. But the ‘hole’ or an electron deficiency is still there in pigment system II. This is fulfilled by the electron coming from photolysis of water. Water here acts as electron donor. It has redox-potential (E’ 0 ) of +0.82 V. This transfer of electron from water probably involves a strong oxidant which is yet unknown and is designated as Z or Yz.
In the above scheme of electron transport the electron ejected from pigment system II did not return to its place of origin, instead it was taken by pigment system I. Similarly, the electron ejected from pigment system I did not cycle back and was consumed in reducing NADP + . Therefore, this electron transport has been called as non-cycle electron transport and the accompanying photophosphorylation as non-cyclic photophosphorylation.
ii. Arrangement of PSI and PSII and various components of non-cyclic electron transport chain when depicted on paper according to their redox-potential values, takes a zig-zag shape like the letter ‘Z’ (Fig. 11.15) hence, non-cyclic electron transport is also called by the name Z-scheme.
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Course: ap®︎/college biology > unit 3.
Term | Meaning |
---|---|
Photosynthesis | The process by which plants, algae, and some bacteria convert light energy to chemical energy in the form of sugars |
Photoautotroph | An organism that produces its own food using light energy (like plants) |
ATP | Adenosine triphosphate, the primary energy carrier in living things |
Chloroplast | The plant cell structure where photosynthesis occurs |
Thylakoids | Disc-like structures within a chloroplast that help absorb light |
Grana | Stacks of thylakoids in a chloroplast |
Chlorophyll | A pigment found in the thylakoid that absorbs light energy and uses it to produce carbohydrates |
Stroma | Fluid-filled space surrounding the grana |
The stages of photosynthesis.
Stage | Location | Events | Requires sunlight? |
---|---|---|---|
Light-dependent reactions | Thylakoid membrane | Light energy is captured by chloroplasts and stored as ATP | Yes |
Calvin cycle | Stroma | ATP is used to create sugars that the plant will use to grow and live | No |
Photosynthesis is a biological process in which plants utilize the available carbon dioxide in the atmosphere to give out oxygen. There is also the presence of a green pigment called chlorophyll is involved in the transfer of unutilized energy to utilizable chemical energy. Mostly the process of photosynthesis involves the utilization of water to release oxygen that we depend on for our lives. Plants which are the only photosynthetic organism to have leaves are viewed as a solar collector packed with photosynthetic cells. For this process to occur, the following raw material should be available; water and carbon dioxide which after entering the leaf cell it produces oxygen found in the atmosphere. During the process water from the soil is taken up by the roots all the way to the leaves via the xylem. In order for the plants not to dry out they use the stoma so that they can exchange gases. Stomata are the only way in which oxygen can get their way out of the leaf. However during this process a great amount of water is lost. This can be witnessed by the cottonwood trees in dry seasons by loosing a total of 100 gallons daily(Kramer & Kozlowski, 1960).
When you consider this process we can classify plants to be carbon sinks because they play a great role of utilizing the carbon dioxide found in oceans and atmosphere. Plants are also involved in production of carbon dioxide through respiration and used by photosynthesis they too convert energy absorbed from the sunlight into chemical energy with covalent bonds and other carbon dioxide sources includes animals. Carbonates in the ocean are formed so that they can balance the presence carbon dioxide and oxygen in the atmosphere. (Smith, 1984).
Carbon dioxide plays different roles in the plants life cycle. Though in many debates it has never been revealed how higher level of carbon dioxide will benefit the Earth. This is true because food crops, flowers and trees depend mostly on carbon dioxide. According to the Voluminous scientist, evidence shows that when the amount of carbon dioxide in the atmosphere rises above the current level the rate of plant growth will increase and enlarge due to more efficient photosynthesis and reduced water loss. Extreme temperatures will not harm plants, there will be faster growth rates and pollutants and excessive nutrients will not injure plants. Increased carbon dioxide in the atmosphere is projected to increase plant productivity, increases the size of a leaf and thickness, the heights of a stem and seed production. This will also lead to an increase in the both numbers and sizes of fruits and flowers (Smith, 1984).
It is also important to note that, though plants through the process of photosynthesis produces oxygen, they will only survive for a few days without oxygen even if everything is provided. If this goes on for sometimes they cannot stay alive. Plants differ from animals due to their abilities to make their own nutrients through the process of photosynthesis. Through this carbohydrates is produced and it’s broken down by plants to get energy. During this process food is created and a reaction is needed so that the created food can be broken down into usable form, and this process requires oxygen, water and nutrients (Wittwer, 1992).
The above discussed can also be applied to people where by they cannot survive without plants. Plants and animals are the two main kingdoms of life. The Earth consists of more than 300,000 species of plant and they can create their own food by means of energy from sunlight. All oxygen is generated by plants. They also make life on the Earth possible by providing humans with food as well as building material. This plant kingdom has different species which can be grouped into; mosses and liverworts, ferns, cone plants and flowering plants (Wittwer, 1992).
According to me life is made possible by plants for example forests and grasslands which supplies oxygen. According Scientists and conservationists if deforestation goes on without control the survival system on the Earth will be injured. In addition to this plants also act as source of food to the people for example fruits, leaves, roots and tuber, seeds and barks too. Plants can also be seen contributing to the survival of the people whereby they make seeds which are transported to different places of the world spreading it. They are sources of energy, People also depend on plants by exchanging gifts in form of flowers, plants be of assistance when it comes to people surviving the harsh conditions.
Plants reduce the amount of noise in the urban setting and add the aesthetic value to the environment. They also contribute towards the ecology of an area by their roots stabilizing the soils which prevent soil erosion. They also reduce the speed of wind which is mostly used by farmers and provide them with income.
With all this, I would conclude that it will be impossible to say that people can survive without plants. This is so because people need oxygen, food, shelter, building material et cetera which is provided by plants. Therefore I will urge everyone to protect all the trees found on Earth by avoiding degrading activities for example; deforestating and polluting forested areas. By doing so, we will be promoting a healthy life to everyone (Wittwer, 1992).
Kramer, P.J. & Kozlowski, T. (1960). Physiology of trees. New York, NY: McGraw Hill.
Smith, W.H. (1984). Pollutant uptake by plants: In air pollution and plant life. New York, NY: John Wiley.
Wittwer, S.H. (1992). Rising carbon dioxide is great for plants. Journal of Biology, 12(6), 1-9.
IvyPanda. (2022, April 1). Photosynthesis As A Biological Process. https://ivypanda.com/essays/photosynthesis-as-a-biological-process/
"Photosynthesis As A Biological Process." IvyPanda , 1 Apr. 2022, ivypanda.com/essays/photosynthesis-as-a-biological-process/.
IvyPanda . (2022) 'Photosynthesis As A Biological Process'. 1 April.
IvyPanda . 2022. "Photosynthesis As A Biological Process." April 1, 2022. https://ivypanda.com/essays/photosynthesis-as-a-biological-process/.
1. IvyPanda . "Photosynthesis As A Biological Process." April 1, 2022. https://ivypanda.com/essays/photosynthesis-as-a-biological-process/.
Bibliography
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IMAGES
COMMENTS
Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
Photosynthesis is one of the most fundamental biological reactions. The chlorophyll bearing plants trap the free energy of sunlight as photons and transform and store it as chemical potential energy by combining CO 2 and water.
Photosynthesis is the ultimate source of all of humankind's food and oxygen, whereas fossilized photosynthetic fuels provide ∼87% of the world's energy. It is the biochemical process that sustains the biosphere as the basis for the food chain.
Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.
Photosynthesis (/ ˌ f oʊ t ə ˈ s ɪ n θ ə s ɪ s / FOH-tə-SINTH-ə-sis) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their activities.
Photosynthesis is a process used by plants, algae, and some bacteria to turn sunlight, water, and carbon dioxide into food and oxygen. This happens in the green parts of plants, mainly the leaves. The green color comes from chlorophyll, a special substance in the leaves that captures sunlight.
In this essay we will discuss about Photosynthesis in Plants. After reading this essay you will learn about: 1. Meaning of Photosynthesis 2. Significance of Photosynthesis to Mankind 3. History 4. Photosynthetic Apparatus 5. Pigments 6. Quantum Requirement and Quantum Yield 7. Mechanism 8. Evidences for Existence of Light and Dark Reactions 9.
Photosynthesis is the process in which light energy is converted to chemical energy in the form of sugars. In a process driven by light energy, glucose molecules (or other sugars) are constructed from water and carbon dioxide, and oxygen is released as a byproduct.
Meaning. Photosynthesis. The process by which plants, algae, and some bacteria convert light energy to chemical energy in the form of sugars. Photoautotroph. An organism that produces its own food using light energy (like plants) ATP. Adenosine triphosphate, the primary energy carrier in living things. Chloroplast.
Photosynthesis is a biological process in which plants utilize the available carbon dioxide in the atmosphere to give out oxygen. There is also the presence of a green pigment called chlorophyll is involved in the transfer of unutilized energy to utilizable chemical energy.