Components of the Ecosystem

Image of Ecosystem components

The region of the earth in which all organisms live is the biosphere. The nonliving features of the environment are abiotic factors and the organisms in the environment are biotic factors. Populations and communities make up an ecosystem. The ecosystem is the base of the biosphere which influences the wellbeing of the entire earth system. … Read more

Virus : Definition, Characteristics and Classification

For proper survival of the plants and animals, they have to struggle against the environment, their different factors and other living organisms. Viruses are microscopic organisms and can be seen only under electron microscope. In nature, any living organism is affected by virus, then it will take a serious turn. Viruses are mysterious biological agents … Read more

Nutrition in Plants: Role and Deficiency Symptoms

Nutrition is the process by which living organisms take their food for maintaining proper growth, metabolisms and replacement of tissue.  Plants nutrition occurs in two phases such as synthesis and assimilation.  Generally, plants nutrition is of two types such as autotrophic plant nutrition and heterotrophic nutrition. Autotrophic Plant Nutrition In autotrophic nutrition, the plant gains … Read more

Lysosome and Its Functions

Lysosomes are single membrane-bound cytoplasmic organelles of most cells filled with a wide variety of hydrolytic enzymes that are involved in intracellular digestion.  The term “Lysosome” comes from the Greek word ‘lysis’, to separate and ‘soma’ body.  Sometimes it can be described as the stomach of the cell. In 1950, Belgian Cytologist Christian Rene de … Read more

Ribosome: Types, Structure and Functions

The ribosome is one of the essential membrane-bound organelles of the cells. It has tiny sphere-shaped structure. It contains protein and ribose nucleic acid (RNA) and provides space for protein synthesis.  It is found in the cytoplasm, mitochondrial matrix, and chloroplast. It is also found on the outer membrane of ER (endoplasmic reticulum) and nucleus. … Read more

Mitochondria : Definition, Structure and Functions

Definition: The word mitochondria come from two Greek words, mito meaning thread and chondrion meaning granule. It has double membrane enclosed rounded or rod-like or filamentous bodies which generate chemical energy in the form of ATP. It is scattered throughout the cytoplasm in most of the cells.
History of Mitochondria: Scientist Kolliker (1850) first observed mitochondria in the striated muscle. Flemming (1882) named it as fila. Rechard Altmann (1897) referred to the mitochondria as Bioplasts. Carl Benda (1897) first called these organelles as mitochondria.
Distribution and occurrence: It is not found in the prokaryotic cell and matured circulated RBC. Generally they are evenly distributed in the cytoplasm. It is also found in the base of the proximal convoluted tubules of nephron. The number of mitochondria present in the cell depends on its activities. Plant cell contains less number of mitochondria than animal cell. A normal liver cell may contain 1000-1600 mitochondria while some oocytes may contain more than 300000 mitochondria. On the other hand, Microasterias algae contain only one mitochondrion
Structure of Mitochondria: Mitochondria have generally spherical or rod-shaped or filamentous structures. It is about 3.0-7.0 µm in length and 0.2-2.0 µm in diameter. It usually consists of two unit membranes, two chambers, mitochondrial matrixs and mitochondrial particles. Every mitochondria is bounded by the double membranes, the outer membrane and inner membrane. Each membrane is made up of lipo-protein and it is about 60 Angstrom thick. The outer membrane is smoothed and covers the mitochondria but the inner membrane remains folded inward at various points to form a number of incomplete partitions which are known as the cristae or mitochondrialis cristae. The two membranes remain 60-80 Angstroms apart from each other. The space between the two membranes is filled up with fluid.