Answer: The evolution of the different light adsorbing pigments used by different phototrophs: The morphology and biochemistry of plastids, light-absorbing pigments of various phototrophs is much more similar to that of cyanobacteria. This is an major evolutionary aspect of phototrops from primitive organisms as per endosymbiotic theory. Chloroplasts of phototrophs (organelle found in plants and photosynthetic green algae, phytoplanktons) are bounded by a double membrane and have an outer and inner membrane & these are major light absorbing pigments from visible spectrum. The inner space is called “stroma,” which contains concentrated enzymes and disc-like sacs called “thylakoids.” The lump of thylakoids is called “granum.” Thylakoid membrane contains the pigments (such as chlorophyll) which capture the solar energy with specific wavelengths and stroma contains the enzymes, which are essential for photosynthesis as seen in cyanobacteria. The major relationship is between the wavelength of light absorbed, oxygenic and anoxygenic photosynthesis, and the particular phototrophic ETS that is used. For instance, light absorbing wavelength is normally changed with purple bacteria & these are the photosynthetic bacteria that contains the beacteriochlorophyll a or b pigments, an evolutionary feature in phytoplanktons, green algae. Presence of these bacteria makes them to appear in different colors ranging from purple to orange. These bacteria are of two types namely, purple sulfur bacteria and purple non- sulfur bacteria. Phototrophs often perform \"oxygenic\" and they carry out electron transport chain. Anoxygenic phototrophs can trap the light energy and synthesize ATP or NADPH. No oxygen is produced during this process, so oxygen is not used as an electron acceptor. They use hydrogen sulfide (H2S) or elemental sulfur as electron acceptor. Metabolically, purple sulfur bacteria are anoxygenic (does not produce oxygen) because they don’t use water as reducing agent during the photosynthesis. Instead, they use elemental sulfur or sulfide as reducing agents & promote simple electron transport chain (ETS). In case of purple non-sulfur bacteria, they typically use hydrogen ions as other compounds in place of water. Chloroplasts are the photosynthetic organelles of plats and they possess double membrane to maintain adequate proton gradient generated from the splitting of water molecules in the presence of light and further to promote ATP synthesis in the presence of ATP synthase. This double membrane profoundly enables maintaining stable position of other cytochrome complexes, plastoquinone complexes of photosystem I & II between stroma and thylakoid membranes as part of evolutionary aspect. Solution Answer: The evolution of the different light adsorbing pigments used by different phototrophs: The morphology and biochemistry of plastids, light-absorbing pigments of various phototrophs is much more similar to that of cyanobacteria. This is an major evolutio.

1. Answer:
The evolution of the different light adsorbing pigments used by different phototrophs:
The morphology and biochemistry of plastids, light-absorbing pigments of various phototrophs is
much more similar to that of cyanobacteria. This is an major evolutionary aspect of phototrops
from primitive organisms as per endosymbiotic theory. Chloroplasts of phototrophs (organelle
found in plants and photosynthetic green algae, phytoplanktons) are bounded by a double
membrane and have an outer and inner membrane & these are major light absorbing pigments
from visible spectrum. The inner space is called “stroma,” which contains concentrated enzymes
and disc-like sacs called “thylakoids.” The lump of thylakoids is called “granum.” Thylakoid
membrane contains the pigments (such as chlorophyll) which capture the solar energy with
specific wavelengths and stroma contains the enzymes, which are essential for photosynthesis as
seen in cyanobacteria.
The major relationship is between the wavelength of light absorbed, oxygenic and anoxygenic
photosynthesis, and the particular phototrophic ETS that is used. For instance, light absorbing
wavelength is normally changed with purple bacteria & these are the photosynthetic bacteria that
contains the beacteriochlorophyll a or b pigments, an evolutionary feature in phytoplanktons,
green algae. Presence of these bacteria makes them to appear in different colors ranging from
purple to orange. These bacteria are of two types namely, purple sulfur bacteria and purple non-
sulfur bacteria. Phototrophs often perform "oxygenic" and they carry out electron transport
chain. Anoxygenic phototrophs can trap the light energy and synthesize ATP or NADPH. No
oxygen is produced during this process, so oxygen is not used as an electron acceptor. They use
hydrogen sulfide (H2S) or elemental sulfur as electron acceptor. Metabolically, purple sulfur
bacteria are anoxygenic (does not produce oxygen) because they don’t use water as reducing
agent during the photosynthesis. Instead, they use elemental sulfur or sulfide as reducing agents
& promote simple electron transport chain (ETS). In case of purple non-sulfur bacteria, they
typically use hydrogen ions as other compounds in place of water. Chloroplasts are the
photosynthetic organelles of plats and they possess double membrane to maintain adequate
proton gradient generated from the splitting of water molecules in the presence of light and
further to promote ATP synthesis in the presence of ATP synthase. This double membrane
profoundly enables maintaining stable position of other cytochrome complexes, plastoquinone
complexes of photosystem I & II between stroma and thylakoid membranes as part of
evolutionary aspect.

2. Solution
Answer:
The evolution of the different light adsorbing pigments used by different phototrophs:
The morphology and biochemistry of plastids, light-absorbing pigments of various phototrophs is
much more similar to that of cyanobacteria. This is an major evolutionary aspect of phototrops
from primitive organisms as per endosymbiotic theory. Chloroplasts of phototrophs (organelle
found in plants and photosynthetic green algae, phytoplanktons) are bounded by a double
membrane and have an outer and inner membrane & these are major light absorbing pigments
from visible spectrum. The inner space is called “stroma,” which contains concentrated enzymes
and disc-like sacs called “thylakoids.” The lump of thylakoids is called “granum.” Thylakoid
membrane contains the pigments (such as chlorophyll) which capture the solar energy with
specific wavelengths and stroma contains the enzymes, which are essential for photosynthesis as
seen in cyanobacteria.
The major relationship is between the wavelength of light absorbed, oxygenic and anoxygenic
photosynthesis, and the particular phototrophic ETS that is used. For instance, light absorbing
wavelength is normally changed with purple bacteria & these are the photosynthetic bacteria that
contains the beacteriochlorophyll a or b pigments, an evolutionary feature in phytoplanktons,
green algae. Presence of these bacteria makes them to appear in different colors ranging from
purple to orange. These bacteria are of two types namely, purple sulfur bacteria and purple non-
sulfur bacteria. Phototrophs often perform "oxygenic" and they carry out electron transport
chain. Anoxygenic phototrophs can trap the light energy and synthesize ATP or NADPH. No
oxygen is produced during this process, so oxygen is not used as an electron acceptor. They use
hydrogen sulfide (H2S) or elemental sulfur as electron acceptor. Metabolically, purple sulfur
bacteria are anoxygenic (does not produce oxygen) because they don’t use water as reducing
agent during the photosynthesis. Instead, they use elemental sulfur or sulfide as reducing agents
& promote simple electron transport chain (ETS). In case of purple non-sulfur bacteria, they
typically use hydrogen ions as other compounds in place of water. Chloroplasts are the
photosynthetic organelles of plats and they possess double membrane to maintain adequate
proton gradient generated from the splitting of water molecules in the presence of light and
further to promote ATP synthesis in the presence of ATP synthase. This double membrane
profoundly enables maintaining stable position of other cytochrome complexes, plastoquinone
complexes of photosystem I & II between stroma and thylakoid membranes as part of

3. evolutionary aspect.