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Algae photosynthesis

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Algae photosynthesis  Empty Algae photosynthesis

Post  liquidg 5th August 2012, 1:06 am

Firstly it is finally becoming apparent that photosynthesis is achieved by excitation from colour wavelengths imbedded with in light, they are realising plants mostly do not need the suns radiation, just the light!

As usual most terms connected with marines can be traced back to Greek wording in some ways as is the word photosythesis.

The Greek lettering( φώτο ) translated is the word photo,for them, it means light,the lettering ( σύνθεσις ) translates to synthesis,meaning,put together!

Algae from Greek terms for algae equates to seaweed covering both unicellular and multi-cellular types.

Okay,now we get into the what makes algae tick in relation to photosynthesizing its intake.

Firstly bacteria that exists with in algae is what gives algae the ability to photosynthesis.

Photosynthetic organisms and this about algae are called photoautotophs,since they can create their own food via photosynthetic conversion of nutrients.

In algae, and cyanobacteria ,photosynthesis uses carbon dioxide and water, releasing oxygen as a waste product,not the oxygen molecule that is the 2O of the H2O,this form of oxygen is available to oxygen dependant life forms to breath extracting it from the water and to a greater extent,it leaves the water helping to saturate the planet with our oxygen needs as well.

Marine algae and these include phytoplankton, are a very diverse group of photosynthetic organisms that process over fifty percent of all the earths CO2 production and converts most of the waste from human society that enters the ocean into silica and oxygen to name just a two invaluable elements from their photosynthetic and associated mechanisms.

These nutrient importing basic life forms that are extremely efficient at absorbing osmotically all those substances we hobbyists Dred from the aquariums waters are able to convert solar energy into chemical energy to import these unwanted bi products before they get a chance to harm our aquarium life if used correctly.

All this work and more takes place in a single cell, from carbon dioxide fixation to TAG synthesis and sequestration, all this takes place within a single algal cell, now that’s something special!

Algae and plant pigments are embedded in special antenna-proteins.

The major antenna pigments in algae include chlorophylls, phycobiliproteins and carotenoids harvest light energy for photosynthesis giving them the variation in the composition and relative abundance of these pigments give algae their distinctive colour depending on which species is visible at the time of course.

Over all plants absorb the light via the pigment chlorophyll,that the accounts for the colour green in many algae.
It must be remembered that with chlorophyll, as most of us know enables plants to capture solar energy and convert it into metabolic energy, has a magnesium atom at its center. But without magnesium, plants could not utilize the sun's light energy.

In actual algae the pigments such as phycocyanin,carotenes and xanthophylls account for most of the green algae forms,then for the red algae their pigment on average is phycoerythrim,for brown algae and diatoms rhodophytes and fucoxauthin give them their part of the wonderful variety of colours seen as photsythetic algae.

Another distinguishing feature of some algae is the large amounts of very long-chain polyunsaturated fatty acids (VLC- PUFAs) as major fatty acid components.

This is a simplified break down of the photosynthesizing algae cell structure.

1.outer membrane
2. intermembrane space
3. inner membrane
A phospholipid outer membrane a phospholipid inner membrane, and an intermembrane space between them.
4. stroma (aqueous fluid)
Within the membrane is an aqueous fluid called the stroma.
The stroma contains stacks (grana) of thylakoids, which are the site of photosynthesis.
5-6. thylakoid membrane
Thyalkoids are tightly folded sheets of membrane or bunched up into round vesciles called intracytoplasmic membranes.
The thylakoid lumen is inside of thylakoid!
7. granum (stack of thylakoids)
8. thylakoid (lamella)
9. starch
10. ribosome
11. plastidial DNA
12. plastoglobule (drop of lipids)

That’s pretty much it to my understanding of the algae cell.

The proteins that equire and store light for photosynthesis are embedded within the cells membranes as described above.

The actual way these are set out are in photosynthetic bacteria, where these proteins are held within the plasma membrane.

These structures can fill most of the interior of a cell, giving the membrane a very large surface area and therefore increasing the amount of light that the bacteria can absorb.

The general equation,not that its that easy to understand is-
Carbon dioxide + electron donor + light energy → carbohydrate + oxidized electron donor
In oxygenic photosynthesis,water is the electron donor and since its hydrolysis releases oxygen, the equation for this process is:

carbon dioxide + water + light energy → carbohydrate + oxygen + water

Often 2n water molecules are cancelled on both sides giving-

carbon dioxide + water + light energy → carbohydrate + oxygen

Other processes substitute other compounds such as arsenite for water in the electron-supply role; the microbes use sunlight to oxidize arsenite to arsenate and this one is-
CO2 + (AsO33–) + photons → (AsO43–) + CO[13]

In plants and algae, photosynthesis takes place in organelles called chloroplasts.
On average all plant cells contain about 10 to 100 chloroplasts and the chloroplast is enclosed by a membrane and as with all the planets plants, here it houses cyanobacteria.

The actual site of photosynthesis is the thykaloide membrane,these take the shape of a flattened disk bounded by a membrane with whats called a lumen of a thylakoid space within it.

This is where the work is done and the membrane contains integral and peripheral membrane protein complexes,like the pigments that absorb light energy,equating to the photosystems!

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