thylakoid
Quick Summary
In biology, a thylakoid is a membrane-bound compartment found inside chloroplasts and cyanobacteria. These are the sites of the light-dependent reactions of photosynthesis.
Thylakoids are typically flattened sacs, and they are often arranged in stacks called grana. The membranes of the thylakoids contain chlorophyll and other pigments that capture light energy. This captured energy is used to split water molecules, releasing oxygen and generating energy-carrying molecules like ATP and NADPH. These molecules are then used in the next stage of photosynthesis to convert carbon dioxide into sugars.1234
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photosynthesisStructural features…hollow disks that are called thylakoids (“saclike”). The chloroplasts of most higher plants have regions, called grana, in which the thylakoids are very tightly stacked. When viewed by electron microscopy at an oblique angle, the grana appear as stacks of disks. When viewed in cross section, it is apparent that…
Read More…hollow disks that are called thylakoids (“saclike”). The chloroplasts of most higher plants have regions, called grana, in which the thylakoids are very tightly stacked. When viewed by electron microscopy at an oblique angle, the grana appear as stacks of disks. When viewed in cross section, it is apparent that…
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metabolismATP formation during photosynthesis…form membrane-bounded closed sacs (thylakoids) often arranged in stacks (grana). Solar energy splits two molecules of H2O into molecular oxygen (O2), four protons (H+), and four electrons.
Read More…form membrane-bounded closed sacs (thylakoids) often arranged in stacks (grana). Solar energy splits two molecules of H2O into molecular oxygen (O2), four protons (H+), and four electrons.
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plantBasic mechanisms…to hollow sacklike disks called thylakoids. Stacks of thylakoids embedded with pigment molecules are called grana. The inner matrix of the chloroplast is called the stroma.
Read More…to hollow sacklike disks called thylakoids. Stacks of thylakoids embedded with pigment molecules are called grana. The inner matrix of the chloroplast is called the stroma.
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chlorophyll…in membranous disklike units (thylakoids) in organelles called chloroplasts.
Read More…in membranous disklike units (thylakoids) in organelles called chloroplasts.
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bacteriaPhototrophic metabolism…of flattened membranous sacs, called thylakoids, the outer surfaces of which are studded with regular arrays of phycobilisome granules. This arrangement, in which pigment aggregates exist on the thylakoid surfaces, is called a photosystem.
Read More…of flattened membranous sacs, called thylakoids, the outer surfaces of which are studded with regular arrays of phycobilisome granules. This arrangement, in which pigment aggregates exist on the thylakoid surfaces, is called a photosystem.
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chloroplastStructural features…presence of closed disks (or thylakoids), is known as the thylakoid membrane. In most higher plants, the thylakoids are arranged in tight stacks called grana (singular granum). Grana are connected by stromal lamellae, extensions that run from one granum, through the stroma, into a neighboring granum. The thylakoid membrane envelops…
Read More…presence of closed disks (or thylakoids), is known as the thylakoid membrane. In most higher plants, the thylakoids are arranged in tight stacks called grana (singular granum). Grana are connected by stromal lamellae, extensions that run from one granum, through the stroma, into a neighboring granum. The thylakoid membrane envelops…
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cellMitochondrial and chloroplastic structure…of flattened, disklike sacs called thylakoids. The space enclosed by the inner membrane is called the matrix in mitochondria and the stroma in chloroplasts. Both spaces are filled with a fluid containing a rich mixture of metabolic products, enzymes, and ions. Enclosed by the thylakoid membrane of the chloroplast is…
Read More…of flattened, disklike sacs called thylakoids. The space enclosed by the inner membrane is called the matrix in mitochondria and the stroma in chloroplasts. Both spaces are filled with a fluid containing a rich mixture of metabolic products, enzymes, and ions. Enclosed by the thylakoid membrane of the chloroplast is…
Read More- cellTrapping of light
chlorophyll molecules embedded in the thylakoid membrane of the chloroplast. The chlorophyll molecules are grouped into antenna complexes, clusters of several hundred molecules that are anchored onto the thylakoid membrane by special proteins. Within each antenna complex is a specialized set of proteins and chlorophyll molecules that form a reaction…
Read Morechlorophyll molecules embedded in the thylakoid membrane of the chloroplast. The chlorophyll molecules are grouped into antenna complexes, clusters of several hundred molecules that are anchored onto the thylakoid membrane by special proteins. Within each antenna complex is a specialized set of proteins and chlorophyll molecules that form a reaction…
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