What Is PQ, PC, & FD in Photosynthesis?

Leaves are organs that collect light for photosynthesis.
••• Image by Flickr.com, courtesy of Jay Denney

Photosynthesis is the process by which certain organisms, including plants, create sugars from the carbon dioxide in the air and the oxygen atom of water. The energy that drives this process comes from light. There are two phases of photosynthesis, the light reactions and the light-independent reactions, also called the Calvin cycle.

Light Reactions

The first stage of photosynthesis is called the “light reactions,” where energy from light is converted into chemical energy in the form of bonds of short-term energy-storing molecules, ATP and NADPH. These molecules provide the energy to make the sugars produced by photosynthesis in the light-independent reactions

Electron Transport Chain

The energy present in a single photon, which is a single particle of light, is too much for a plant to use at once. Instead, when certain chlorophyll molecules absorb a photon, it excites a pair of electrons, which are then passed through a series of molecules that make up the chain, which indirectly leads to the production of ATP and NADPH.

PQ

PQ, short for plastoquinone, is a molecule in the electron transport chain. It is the second molecule in the chain, receiving the electron pair from pheophytin and passing it on to the cytochrome b6f complex.

PC

PC, short for plastocyanin, is a copper-containing compound in the electron transport chain that accepts the pair of electrons from the cytochrome b6f complex. Plastocyanin’s dependence on copper is one reason that copper is a vital nutrient for plants.

FD

FD, short for ferredoxin, is a protein that is not involved in the electron transport chain, but is still involved in the light reactions. This enzyme moves electrons excited by a different molecule of chlorophyll than the electrons from the electron transport chain to the enzyme that stores this light-derived energy in NADPH.

Related Articles

What Is the Role of Pigments in Photosynthesis?
What Provides Electrons For the Light Reactions?
Describe What a Photosystem Does for Photosynthesis
What Happens in the Light Reaction of Photosynthesis?
What Is the Sun's Role in Photosynthesis?
What Role Does Chlorophyll Play in Photosynthesis?
Two Stages of Photosynthesis
10 Facts on Photosynthesis
What Is Reduced & Oxidized in Photosynthesis?
How Does a Plant Convert Light Energy to Chemical Energy?
What Is Nadph in Photosynthesis?
What Are the Functions of Photosynthesis?
Key Differences Between C3, C4 and CAM Photosynthesis
Organelles Involved in Photosynthesis
Materials Needed for Photosynthesis
What Four Accessory Pigments Are Necessary for Photosynthesis...
What Is the Photosynthesis Equation?
What Types of Molecules Catalyze RNA Splicing?
What Are Light Dependent Reactions?

Dont Go!

We Have More Great Sciencing Articles!