[Hayi Gosain]

The primary function of photosynthesis is to convert solar energy into chemical energy and then store that chemical energy for future use. For the most part, the planet’s living systems are powered by this process.

Photosynthesis is important to plants because it allows them to make glucose, which is needed to make energy and cellular structures. Photosynthesis also makes oxygen, which plants and animals both need to carry out cellular respiration to make ATP (a complex organic chemical that provides energy). During photosynthesis, carbon dioxide is fixed into an organic molecule using light energy from the sun. Those organic molecules are then converted to glucose, and oxygen is produced as a waste product. The cell can then use glucose in cellular respiration to make ATP, or use glucose itself as a structural molecule for growth and repair.

Green plants take carbon, hydrogen and oxygen from the molecules of carbon dioxide and water, and then recombine them into a new molecule called glucose. This happens in the presence of sunlight, of course. Energy is stored in the bonds of the glucose molecule. Glucose is a fairly simple sugar, easy to break down.Respiration happens in regions of a cell called mitochondria. The chemical reactions are the reverse of photosynthesis, using a glucose molecule and six oxygen molecules (12 atoms) as inputs. Energy is released along with some carbon dioxide and water.

Trees and other green plants practice respiration, too, just like animals, but they also practice photosynthesis. This is why ecologists categorize green plants as “producers” and most every other life form as a “consumer.” It’s about the energy. Oxygen is a byproduct of photosynthesis and, correspondingly, carbon dioxide the byproduct of respiration. Trees are often credited as the major oxygen generator for the planet, but that would be false. Most of the planet is covered with water and the collective photosynthesis of lowly algae is the true oxygen machine.Much of the basic structural material of plants and wood is cellulose, which is an especially complex sugar. The constituent molecules of carbon, hydrogen and oxygen can be recombined to form lots of useful chemicals such as ethanol, perfumes, bioplastics, clothing fabrics and a range of industrial ingredients. It’s generally agreed that sources from within renewable living ecosystems have distinct advantages over using the ancient materials that make up fossil fuels.

Conclusion: Photosynthesis is the source of energy and food for all organisms directly and indirectly. Herbivores depend directly on plants whereas carnivores depend on herbivores which feed on plants. So, it sustains all the food chains in an ecosystem.

[Hayi Gosain]

Mitochondria – Powerhouse of cell:

Mitochondria is a double membrane-bound semiautonomous organelle present in the cytoplasm of the cell which possesses its genetic material and ribosomes. The proteins synthesized by the proteins in mitochondria are utilized to generate adenosine triphosphate (ATP) from the food. This ATP acts as the energy currency of the cell, because of which the whole cell and body get energy.Thus, mitochondria are called the powerhouse of the cells.

Structure of Mitochondria

The mitochondrion is a double-membraned, rod-shaped,structure found in both plant and animal cell.Its size ranges from 0.5 to 1.0 micrometre in diameter.The structure comprises an outer membrane, an inner membrane, and a gel-like material called the matrix.The outer membrane and the inner membrane are made of proteins and phospholipid layers separated by the intermembrane space.The outer membrane covers the surface of the mitochondrion and has a large number of special proteins known as porins.

Cristae:

The inner membrane of mitochondria is rather complex in structure. It has many folds that form a layered structure called cristae, and this helps in increasing the surface area inside the organelle. The cristae and the proteins of the inner membrane aid in the production of ATP molecules. The inner mitochondrial membrane is strictly permeable only to oxygen and ATP molecules. A number of chemical reactions take place within the inner membrane of mitochondria.

Mitochondrial Matrix

The mitochondrial matrix is a viscous fluid that contains a mixture of enzymes and proteins. It also comprises ribosomes, inorganic ions, mitochondrial DNA, nucleotide cofactors, and organic molecules. The enzymes present in the matrix play an important role in the synthesis of ATP molecules.

• This reply was modified 1 year, 10 months ago by  Hayi Gosain.