Here, the Calvin cycle is used to describe the light-independent reactions.The second phase is known as reduction and requires ATP and NADPH.Water is then transported to the leaves (and other parts of the plant) through the xylem (one of the plants vascular tissues).
This stage is fueled by ATP which acts as the source of energy.
For photoautotrophs, chlorophyll is a very important pigment.
Here, light energy obtained from the sun is used to produce food material (organic material) from carbon-dioxide and water.
As mentioned, all photoautotrophs have chlorophyll. While some like cyanobacteria may not have a chloroplast that contains the chlorophyll, they have chlorophyll in place to capture light energy to be used for photosynthesis.
In higher plants, photosynthesis takes place in the mesophyll layer of the leaf where chloroplasts are located.
Carbon-dioxide required for photosynthesis gets into the mesophyll layer and into the chloroplast through small openings on the leaves known as stomata.These organisms live in different environments and use different mechanisms (and material) to produce energy.Basically, phototrophy involves the use of light energy (from the sun) for photosynthesis.Since autotrophs do not depend on organic matter and are capable of making their own food from inorganic sources, they occupy the base of the food chain (first trophic/nutritional level) with herbivores and carnivores (as well as omnivores) occupying the second and third trophic levels respectively.While there are a wide variety of organisms that are classified as autotrophs, there are two main types based on how they produce their food.- Chlorophyll a is the most common chlorophyll and can be found in the majority of the photoautotrophs including cyanobacteria, higher plants and algae.Chlorophyll (a) captures blue-violet and orange-red light (at 675nm) while reflecting green light (thus appearing green in color).In plants, the light-independent reactions take place in the absence of sunlight.Because the first phase (light dependent reactions) successfully produced energy in the form of ATP and NADPH, sunlight is no longer required given that these sources of energy provide the required energy for sugar synthesis.Because of their ability to make their own food, autotrophs are also commonly refered to as primary producers and thus occupy the base of the food chain.They vary widely from those found on land (soil) to those that live in aquatic environments.