Photosynthesis and cellular respiration are biochemical pathways;

Combusion of fossil fuels to generate energy for electricity, heating and cooling, industrial processes, and transportation accounts for over 80 percent of greenhouse gas emissions. ( is a chemical reaction wherein atmospheric oxygen reacts with carbon and hydrogen in fuel, creating carbon dioxide, water vapor, and energy in the form of heat and light.

Photosynthesis provides the chemical energy needed to produce these compounds.

Expose the plant to sunlight and after some time youwill see bubbles of oxygen gather on the test tube then collect to form a larger bubble.
Photosynthesis ***
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In some way, respiration can be considered the opposite of the photosynthesis: theorganism demolishes sugars to obtain the energy necessary for its biochemical processes(figure 16).


Chemistry for Biologists: Photosynthesis

To know that photosynthesis can convert light energy into chemical energy.

Plants, algae, and some bacteria are capable of carrying out photosynthesis. They could get the immediate benefit of portable ATP molecules to drive biochemical reactions. However, the production of ATP in photosynthesis is also connected to carbon capture. Carbon dioxide from the air is incorporated into carbohydrate molecules. This conversion happens in a series of reactions called "dark reactions", because they keep happening even without sunlight. The carbohydrates can be stored, long-term, and later they can be used as energy sources via glycolysis and the citric acid cycle.


Photosynthesis is a process used by plants and other organisms ..

Light reaction and photophosphorylation
Photosystems are of two types: PS I P700, PS II P680. Components of photosystem I and II transfer the electrons from water to NADP. Light is absorbed by these photosystems and electrons are transferred from water to NADP. Photophosphorylation is a process where the light energy captured by the photosynthetic organisms is transformed into the phosphate bond energy of ATP. During the transfer of electrons, ATP is synthesized. Electron flow is cyclic. As a result oxygen is not released and ATP is formed as a result of proton gradient created by Cytochrome bf pump.

Cyanobacteria and the evolution of photosynthesis

Chloroplast structure
Chloroplast is a plant subcellular organelle where photosynthesis takes place. Outer membrane of chloroplast is permeable. Inner membrane encloses stroma. Thylakoid is flattened membrane surrounded vesicle. This is the place where light reaction occurs. In stroma, fluid surrounding the thylakoids is the place where the dark reaction occurs. Chlorophylls are the green pigments; they are present in the thylakoid membrane of chloroplast. They absorb deep blue and red light. Secondary light absorbing pigments are called accessory pigments. They are carotenoids and phycobilins. Photosystems are the light absorbing pigments of thylakoid membrane arranged in functional sets.

The Process of Photosynthesis in Plants: An Overview

In biology, energy is needed in order to drive all sorts of biochemical processes. Energy is needed to stay alive. There are plenty of energy sources on earth. Tectonic forces release massive amounts of heat and drive the conversion of some minerals into gaseous products; for example, metal sulfides such as zincblende can be converted to gaseous hydrogen sulfide, H2S. Sometimes, all that heat and gas finds its way to the earth's surface in the form of volcanoes. In the oceans, some marine organisms get their energy from gases released from volcanic vents, such as methane and hydrogen sulfide. However, sunlight is an even more abundant source of energy over most of the earth's surface. In photosynthesis, light energy is absorbed and used to make ATP. Remember, ATP is like a portable battery pack in biology; it can travel to different parts of a cell where it can be used to power uphill steps in biochemical reactions.