Mitochondria and Chloroplasts – Mt Hood Community College Biology
ions and membrane molecules between grana and stroma thylakoid of thin- sectioned chloroplasts in which the internal thylakoid lustrate in a simple diagram how PSI and PSII are . beginning of a membrane branch that links the stroma. What is the difference between Grana and Thylakoid? Grana and thylakoids are two components found in chloroplast and are involved in the light “ Chloroplast granum diagram” by BlueRidgeKitties (CC BY ) via Flickr. What is the difference between Grana and Thylakoid? Grana are the stacks of thylakoids inside the chloroplast. Thylakoid is the pillow-shaped 2. “Thylakoid disc diagram”by BlueRidgeKitties (CC BY ) via Flickr. Save.
The chloroplast SRP can interact with its target proteins either post-translationally or co-translationally, thus transporting imported proteins as well as those that are translated inside the chloroplast.
Difference Between Grana and Thylakoid | Grana vs Thylakoid
Some transmembrane proteins may also spontaneously insert into the membrane from the stromal side without energy requirement. These include light-driven water oxidation and oxygen evolutionthe pumping of protons across the thylakoid membranes coupled with the electron transport chain of the photosystems and cytochrome complex, and ATP synthesis by the ATP synthase utilizing the generated proton gradient.
The water-splitting reaction occurs on the lumenal side of the thylakoid membrane and is driven by the light energy captured by the photosystems.
This oxidation of water conveniently produces the waste product O2 that is vital for cellular respiration. The molecular oxygen formed by the reaction is released into the atmosphere. Electron transport chains[ edit ] Two different variations of electron transport are used during photosynthesis: Cyclic electron transport or Cyclic photophosphorylation produces only ATP.
The noncyclic variety involves the participation of both photosystems, while the cyclic electron flow is dependent on only photosystem I. In cyclic mode, the energized electron is passed down a chain that ultimately returns it in its base state to the chlorophyll that energized it. The carriers in the electron transport chain use some of the electron's energy to actively transport protons from the stroma to the lumen.
During photosynthesis, the lumen becomes acidicas low as pH 4, compared to pH 8 in the stroma. Source of proton gradient[ edit ] The protons in the lumen come from three primary sources.
Photolysis by photosystem II oxidises water to oxygenprotons and electrons in the lumen.
The transfer of electrons from photosystem II to plastoquinone during non-cyclic electron transport consumes two protons from the stroma.
These are released in the lumen when the reduced plastoquinol is oxidized by the cytochrome b6f protein complex on the lumen side of the thylakoid membrane. From the plastoquinone pool, electrons pass through the cytochrome b6f complex. This integral membrane assembly resembles cytochrome bc1. The reduction of plastoquinone by ferredoxin during cyclic electron transport also transfers two protons from the stroma to the lumen.
ATP generation[ edit ] The molecular mechanism of ATP Adenosine triphosphate generation in chloroplasts is similar to that in mitochondria and takes the required energy from the proton motive force PMF. The PMF is the sum of a proton chemical potential given by the proton concentration gradient and a transmembrane electrical potential given by charge separation across the membrane.
Compared to the inner membranes of mitochondria, which have a significantly higher membrane potential due to charge separation, thylakoid membranes lack a charge gradient. The area surrounded by the folds is called the mitochondrial matrix.
The cristae and the matrix have different roles in cellular respiration. In keeping with our theme of form following function, it is important to point out that muscle cells have a very high concentration of mitochondria because muscle cells need a lot of energy to contract.
Figure 14 This transmission electron micrograph shows a mitochondrion as viewed with an electron microscope. Notice the inner and outer membranes, the cristae, and the mitochondrial matrix.
Thylakoid - Wikipedia
Carbon dioxide CO2water, and light energy are used to make glucose and oxygen in photosynthesis. This is the major difference between plants and animals: Plants autotrophs are able to make their own food, like glucose, whereas animals heterotrophs must rely on other organisms for their organic compounds or food source.
The fluid enclosed by the inner membrane and surrounding the grana is called the stroma. Figure 15 This simplified diagram of a chloroplast shows the outer membrane, inner membrane, thylakoids, grana, and stroma. Surface Area for Photosynthesis Grana increases the surface area for photosynthesis Individual thylakoids have a lesser surface area for the process of photosynthesis in comparison to the stacked structure grana.
Summary — Grana vs Thylakoid Photosynthesis is a vital process for maintaining the energy flow in organisms via food chains.
Difference Between Grana and Thylakoid
It is the only independent process in which carbon dioxide can be converted to glucose and energy. Chloroplasts are the structural sites of photosynthesis, where sunlight is converted into food by plants.Photosynthesis Light reaction, Calvin cycle, Electron Transport 3D Animation
This process is carried out in two main ways: Grana are thylakoids are two structures in chloroplasts which are involved in photosynthesis. Thylakoids are the number of flattened sacs inside a chloroplast, bound by pigmented membranes on which the light reactions of photosynthesis take place.
Grana are the stacks of thylakoids organized inside the stroma to increase the surface area for light dependent photosynthesis. Light dependent reactions of photosynthesis mainly occur in thylakoid membranes.
This is the difference between grana and thylakoid. Minami, E, and A Watanabe.