The cyclic mode is stimulated when NADPH levels are high.

As we can see, there is a close relationship between the action spectrum and absorption spectrum of photosynthesis. There are many different types of photosynthetic pigments which will absorb light best at different wavelengths. However the most abundant photosynthetic pigment in plants is chlorophyll and therefore the rate of photosynthesis will be the greatest at wavelengths of light best absorbed by chlorophyll (400nm-525nm corresponding to violet-blue light). Very little light is absorbed by chlorophyll at wavelengths of light between 525nm and 625 (green-yellow light) so the rate of photosynthesis will be the least within this range. However, there are other pigments that are able to absorb green-yellow light such as carotene. Even though these are present in small amounts they allow a low rate of photosynthesis to occur at wavelengths of light that chlorophyll cannot absorb.

NADPH in photosynthesis? | Yahoo Answers

Photosynthesis consists of light-dependent and light-independent reactions.

How is ATP used in photosynthesis? - Quora

Cyanobacteria are prominent vessels for synthetic biology approaches, recently receiving attention from NASA as polymer construction hosts. Even though it might be some time before seeing photosynthetic organisms doing large scale production in space (or in Mars, according to our 2015 iGEM team), the principle remains the same: light, CO2 and water—feedstock plentifully available in a resource-limited planet—are captured by photosynthetic microbial cell factories to produce any fuel, nutrient, or pharmaceutical.

The Energy in the Atp and Nadph Molecules is Used ..

Hijacking electrons from photosynthesis is a promising bioengineering alternative, especially in the cases where reducing power and co-factor availability are limiting. This study shows that Synechocystis is receptive to this practice, and paves the way for further metabolic engineering work, aiming to produce more and commercially interesting compounds.

Photosystem I is coupled to an  to produce reducing power in the form of NADPH/H+.

Chlorophyll is used in photosynthesis; ..

Components of cyanobacterial photosynthetic and hydrogen-producing machinery are among the best studied protein complexes that gave us insight into the processes of energy conversion and utilization. They laid the ground for numerous semi-artificial devices for hydrogen production. Their design is based on coupling a photosensitizer (PS I or PS II complexes) and a hydrogen-producing catalyst (noble metal or hydrogenase) in a way that is conducive to the process of light-driven electron transfer from the photosensitizer to the hydrogen-producing part of the system.

These proteins that gather light for photosynthesis are embedded within cell membranes.

photosynthesis and atp and nadph - …

Light reaction and photophosphorylation
Pigments embedded on thylakoid membranes form photosystems. There are of two types: PS I P700, PS II P680. Components of photosystem I and II transfer the electrons from water to NADP via cyclic electron transfer or non-cyclic electron transfer. During electron transfer, the light energy captured by the photosynthetic organisms is transformed into the phosphate bond energy of ATP. This is called photophosphorylation. NADPH is generated during non-cyclic electron transfer.

The reducing power is provided by NADPH, which acquired energized electrons in the light reactions.

Two Photosystems Generate a Proton Gradient and NADPH …

Photosynthesis occurs inside chloroplasts. Chloroplasts contain chlorophyll, a green pigment found inside the thylakoid membranes. These chlorophyll molecules are arranged in groups called photosystems. There are two types of photosystems, Photosystem II and Photosystem I. When a chlorophyll molecule absorbs light, the energy from this light raises an electron within the chlorophyll molecule to a higher energy state. The chlorophyll molecule is then said to be photoactivated. Excited electron anywhere within the photosystem are then passed on from one chlorophyll molecule to the next until they reach a special chlorophyll molecule at the reaction centre of the photosystem. This special chlorophyll molecule then passes on the excited electron to a chain of electron carriers.

The enzyme , a flavoprotein containing protein, reduces NADP+ to NADPH.

Light and dark reactions in photosynthesis - …

Efficiency PS I—Pt system was demonstrated on platinized nanoparticles of PS I from Thermosynechococcus elongatus that were capable of maintaining hydrogen production up to 5.5 μmol/(mg chlorophyll × h) [48]. Electron transport from sodium ascorbate via PS I to cytochrome c6 was driving hydrogen formation on platinum. Since this system used PS I from thermophilic cyanobacterium, hydrogen production was observed at temperatures up to 55˚C, and the device could be used intermittently for over 85 days.