Chloroplasts are not necessarily needed for photosynthesis

From the perspective of endosymbiotic, the chloroplasts in modern higher plants or lower eukaryotic photosynthetic algae actually come from cyanobacteria. In other words, in the long evolutionary process, the ancestors of plant cells swallowed cyanobacteria and found that they could photosynthesize to provide energy, so they kept them in their bodies. After a long time, cyanobacteria gradually lose other functions that have nothing to do with photosynthesis, and the whole becomes a part of the plant cell.

This part is defined as chloroplasts.

If you are interested, you can take a look at the chloroplasts of Sea Slug. This guy lives by eating seaweed, but not digesting seaweed. Instead, they swallow the chloroplasts of the seaweed and keep them in their bodies.

Let the chloroplasts of the seaweed photosynthesize to provide energy and carbohydrates to the sea slug.

Think of seaweed as a straw; A lot of chloroplasts are lined up in straws; When Sea Slug eats it, it sucks the chloroplast out of the straw.

It's good that we can do the same, eat some seaweed and bask in the sun.

Photosynthesis, or photosynthesis, is a biochemical process in which plants, algae, and certain bacteria use photosynthetic pigments to convert carbon dioxide (or hydrogen sulfide) and water into organic matter and release oxygen (or hydrogen) under the irradiation of visible light.

Raw materials: water, carbon dioxide.

Conditions: Light, chlorophyll.

One cannot be the other.

Photosynthesis requires pigments that capture light energy!

photons, carbon dioxide, and water.

Photosynthetic enzymes and pigments.

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Conditions: Light, photosynthetic pigments, photoreactive enzymes. Location:

The thylakoid membrane of chloroplasts. (Pigment) Photosynthesis Reaction: (Raw Materials) Light (Product) Water + Carbon Dioxide Organic Matter (Mainly Starch) + Oxygen ( Photosynthetic chloroplasts are the conditions) Chloroplast Process:

Photolysis of water: 2H2O4[H]+O2 (catalyzed by light and pigment skin in chloroplasts). Synthesis of ATP:

ADP+PI+Energy ATP (catalyzed by light, enzymes and pigments in chloroplasts). Influencing factors: light intensity, CO2 concentration, water supply, temperature, pH, mineral elements, etc.

Significance: Photolysis of water, production of oxygen. Converts light energy into chemical energy to produce ATP, which provides energy for carbon reactions.

Using the hydrogen ions of the product of water photolysis, Nadph (reduced coenzyme) is synthesized to provide the reducing agent Nadph (reduced coenzyme) for carbon reaction, and Nadph (reduced coenzyme) can also provide energy for carbon reaction. The detailed process is as follows: The system is composed of a variety of pigments, such as chlorophyll a, chlorophyll b, carotenoids, etc.

Not only does it broaden the spectrum of photosynthesis, but other pigments can also absorb excessive strong light and produce the so-called photoprotection effect. In this system, when a photon hits a pigment molecule in the system, the electrons will move between the molecules until the center of the reaction, as shown in **. There are two reaction centers, the absorption spectrum of the first photosystem reaches a peak at 700 nm, and the second system peaks at 680 nm.

The reaction center is composed of chlorophyll a and a specific protein (chlorophyll a in this case is due to its location rather than structure), and the type of protein determines the wavelength of absorption by the reaction center. After the reaction center absorbs a specific wavelength of light, chlorophyll a excites an electron, and the enzyme next to it causes the water to be cleaved into hydrogen ions and oxygen atoms, and the excess electrons are used to make up for the lack of chlorophyll a molecule. Chlorophyll A then produces ATP and Nadph through a process as shown in the figure

Unable to perform full photosynthesis. Photosynthesis is divided into light reaction and dark reaction phase, where the light reaction phase is carried out in the chloroplast, while the dark reaction is carried out in the cytoplasmic matrix, and when the chloroplast is out of body, only the light reaction phase can be carried out.

Chloroplasts are the most important and ubiquitous plastids in plant cells, and they are the organelles that carry out photosynthesis. Chloroplasts use their chlorophyll to convert light energy into chemical energy and CO2 and limb water into sugar. Chloroplasts are the world's lowest-cost biofactories that create the most material wealth.

It can be said that the energy required for almost all life activities is the sun (light energy).

Green plants are the main energy converters because they contain chloroplasts, which are energy-converting organelles, which use light energy to assimilate carbon dioxide and water, synthesize energy-storing organic matter, and produce oxygen. Therefore, the photosynthesis of green plants is the fundamental source of the survival, reproduction and development of organisms on the earth.

Chloroplasts may have originated from ancient cyanobacteria because of the chlorophyll found in cyanobacteria. Some ancient eukaryotes survived by devouring other organisms, and some of the cyanobacteria they swallowed were not digested and instead relied on the domestic waste of the devourers to make nutrients.

The chloroplasts of higher plants are found in the cytoplasmic matrix. Chloroplasts are generally green, flat, fast-flowing, ellipsoidal or spherical, and their morphology and distribution can be observed with a high-powered optical microscope.

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