The Process of Photosynthesis in Plants (With Diagram) ..

If the light intensity is not a limiting factor, there will usually be a shortage of NADP+ as NADPH accumulates within the stroma (see light independent reaction). NADP+ is needed for the normal flow of electrons in the thylakoid membranes as it is the final electron acceptor. If NADP+ is not available then the normal flow of electrons is inhibited. However, there is an alternative pathway for ATP production in this case and it is called cyclic photophosphorylation. It begins with Photosystem I absorbing light and becoming photoactivated. The excited electrons from Photosystem I are then passed on to a chain of electron carriers between Photosystem I and II. These electrons travel along the chain of carriers back to Photosystem I and as they do so they cause the pumping of protons across the thylakoid membrane and therefore create a proton gradient. As explained previously, the protons move back across the thylakoid membrane through ATP synthase and as they do so, ATP is produced. Therefore, ATP can be produced even when there is a shortage of NADP+.

The Light-Dependent and Light-Independent Reactions

Photosynthesis consists of light-dependent and light-independent reactions.

The light-independent reactions of photosynthesis


We cannot fully study photosynthesis without knowing more about the structure of a leaf. The leaf is adapted to play a vital role in the process of photosynthesis.


Mosts green plants have leaves that are broad, flat and exposed to capture as much of the sun's energy (sunlight) needed for photosynthesis.

The network of veins in the leaf also carry water from the stems to the leaves. Glucose produced is also sent to the other parts of the plant from the leaves through the veins. Additionally, the veins support and hold the leaf flat to capture sunlight.

The stomata (tiny holes underneath the leaf) allows air in and out of the leaf. Stomata (single is called stoma) is usually at the bottom surface of the leaf but some plant species have them on the upper surface whiles other have them on both sides.
The stomata closes in the night to retain gases and moisture in the leaf cells, and opens during the day for gaseous exchange to continue.

Below is a close diagram of the leaf structure:




Take a good look at the diagram and the various parts of the leaf structure. It will be very useful on the next page.

Photosynthesis Explained with a Diagram - BiologyWise

The light dependent reaction requires light energy from the Sun which is composed of a range of wavelengths (colours). During the process light energy is converted into chemical energy by forming the energy-carrying molecule ATP and and the hygrogen-carrying molecule NADPH.

Plants cells contain a number of structures that are involved in the process of photosynthesis:
Diagram of a plant cell involved in production of glucose from photosynthesis

Light and dark reactions in photosynthesis ..

Photosynthesis is the process used by plants, algae and certain bacteria to harness energy from sunlight into chemical energy.
Photosynthesis is the production of organic compounds from This diagram represents the 5 Carbon dioxide in air is the major source for the leaves of plants.
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms.
Photosynthetic cells are able to use solar energy to synthesize energy In plants, photosynthesis takes place in Diagram of a chloroplast.
Photosynthesis. Photosynthesis [photosynthesis: The chemical change that occurs in the leaves of green plants. It uses light energy to convert carbon dioxide.
The Process of Photosynthesis in Plants! Introduction: Life on earth ultimately depends on energy derived from sun. Photosynthesis is the only process of biological.
Photosynthesis in Plants. In plants, photosynthesis occurs mainly within the leaves. Since photosynthesis requires carbon dioxide, water, and sunlight.
Photosynthesis is a process used by plants in which energy Create Biology Diagram examples like this template called Photosynthesis Diagram that you can easily.
eden project Photosynthesis: how plants help us survive Carbon dioxide 'his gas from th air is taken in through the Water Sunlight Carbon dioxide.
How CAM Plants are able to fix carbon at night so we saw that in classic C3 photosynthesis And and we saw it here in our CAM-4 diagram.

The process of photosynthesis actually becomes possible due to the chlorophyll that is present in plant leaves.

Chapter 19, The Light Reactions of Photosynthesis.

The structure of the chloroplast helps improve the production of NADPH and ATP which are both used in the light-independent reaction in the chloroplast stroma. The fluid stroma contains the enzymes for the Calvin cycle, the close association of the key molecules (e.g., PSII, PSI and ATP synthase) in the thylakoid membrane allows the efficient flow of electrons through the memebrane and the movement of protons (H+) across the membrane using carrier molecules and ATP synthase. The large number of thylakoids increases the total surface area for the absorption of sunlight and the number of key molecules used for the production of NADPH and ATP. The small size of the thylakoid lumen allows for the production of a H+ concentration gradient between lumen and stroma where the energy is used to produce ATP. The step numbers in the Table 2 correspond to the numbers in Figure 1.

Our next step toward understanding photosynthesis is to look more closely at how the two stages work, beginning with the light reactions.

Photosynthesis (Light Reactions) - YouTube

We know; it's very annoying.

As you’ve probably gathered by now, the light-dependent reactions fuel the second stage of photosynthesis called the light-independent reactions.