Author Archives: admin

Biology Terms and Definitions

Terms of Biology Ecology: Study of organisms in relation to environment is called ecology. Physiology: Study of functions of different parts of body is called physiology. Histology: Study of tissues with the help of microscope is called histology. Genetics: Study of hereditary characters and their inheritance is called genetics. Zoogeography: Study of geographical distribution of animals on earth is called ...

Read More »

Important Point of The Chapter bacteria And Viruses

ADDITIONAL RELATED READINGS Taxonomy is the branch of biology which deals with the naming and classification of individuals. The arrangement of organisms into systematic groups is called as classification. More than 1.5 million species of animals and more than 0.5 million species of plants are known. All organisms are related to one another at some point in their evolutionary histories. ...

Read More »

Classification of virus Notes

CLASSIFICATION OF VIRUSES Different types of plant, animal and bacterial viruses are classified on the basis of morphology, cover and nucleic acid properties. Genetic Material: The genetic material may be DNA or RNA Cover: The genetic material may be naked, enveloped or complex. Morphology: On the basis of morphology viruses are classified into rod shaped (T.M.V), spherical (poliovirus), tadpole like ...

Read More »


The bacteriophage replicates only inside the bacterial cell. There are many steps in replication. Attachment (Adsorption) of Phage to the Host Cell: First of all the bacteriophage attaches to the bacterial cell at receptor site. The receptor sites are present on the cell wall of bacterium. During attachment, week chemical union occurs between virion and the receptor site. Penetration: In ...

Read More »

Diseases Caused by Viruses

DISEASES CAUSED BY VIRUSES Small Pox: Virus: It is caused by poxviruses. This virus is DNAenveloped. History: This disease occurred as epidemic in China in 12th century B.C. Until the early 20th century, it was common. Symptoms / Effects: This disease results in the formation of raisedfluid-filledvesicles on the body. These become pustules later on and form pitted scars, the ...

Read More »

Structure and Shape of bacteriophage

These have two shapes (structural forms): Cubical: These are regular solid or icosahedral (having 20 triangular faces). Helical Symmetry: They are rod shaped. Many phages consist of head and tail. The heads are polyhedral but tails are rod shaped. STRUCTURE OF BACTERIOPHAGE Bacteriophage meaning bacteria eater. Earlier workers studied few phages that infect Escherichia coli. Of these the best phages ...

Read More »

facts about cells 11 graders

ADDITIONAL RELATED READINGS ABOUT CELL A cell is the structural and functional unit of life. Discovery of cell is linked with the invention of microscope because most of the cells are microscopic. Robert Hooke discovered the cell in 1665 under his self-made compound microscope. According to Hooke, cell is an empty space surrounded by thick walls. He published his work ...

Read More »


Precipitation is condensation of water vapours in the form of rain, hail, snow etc.Precipitation (rainfall, snowfall) is the major source of soil moisture. All soil moisture is derived from precipitation. It is the driving force of the water cycle as well. Precipitation begins as water vapour derived from the surfaces of oceans in the atmosphere which condense to form clouds ...

Read More »

Diversity of Mammalia

Diversity of Mammals

Current vertebrates have following attributes: 1. They have hair on the body. 2. They have mammary organs. 3. They have specific teeth. They have heterodont dentition 4. Three center auto ossicics are available. 5. Stomach is available in them. 6. Their skin has sweat, sebaceous. fragrance organs. 7. Theirheart is four-chambered. 8. They have extensive cerebral cortex. The zoologists differ ...

Read More »

characteristics, types and functions Permanent tissue

parenchyma tissue Structure

characteristics, types and functions Permanent tissue Attributes of lasting tissue:    Changeless tissues are subsidiaries of meristematic tissue They are develop tissue and the cell have lost the limit of cell division.   Sorts of changeless tissue    Straightforward lasting tissue Complex changeless tissue Secretory tissue 1. Straightforward lasting tissue    Straightforward lasting tissue is made out of single kind ...

Read More »
Distributed by