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 »

LIFE CYCLE OF BACTERIOPHAGES ( LYTIC AND LYSOGENIC CYCLE)

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 »

Leptosporangium vs Eusporangium

Leptosporangium vs Eusporangium – In the first step in leptosporangium, the epidermal cells of leaf or sporangiophore some sperm cells behave as superficial initial cells. Superficial initial cell divides periclinally due to which to form two celled body structures. Secondly, the outer cell as sporangial initial cell and inner cell that does not take part in further division as stalk ...

Read More »

Sporangium and Different Spore Types

Sporangium Sporangium has been derived from modern Latin word “spora” means spores and classical Greek word “angeion” which means vessel. So, sac like structure, which develops spores as tetrad after meiosis of spore mother cell. Spore: Reproductive unit of a plant body which upon germination to form a new plant body. Types of Sporangium (Depending upon Organization with Position, Shape, ...

Read More »

Female Cone Lecture

Female Cone Female cone has whorl of loosely arranged megasporophylls. In cycas, whereas in pinus there is in compact arrangement of megasporophylls, behave ovuliferous scale. So, in pinus female cone behave as inflorescence due to aggregation of female flower (ovuliferous scale). Each megasporophyll quite large in size, bearing 1-5 pairs of big ovules of cycas whereas, in pinus there are ...

Read More »
Distributed by name369.com