9th grade biology test

Acoelomata In acoelomata, the body cavity is not seen. The space between outer body wall (skin) and inner body wall (alimentary canal) is occupied by a tissue called mesenchyme. This condition is seen in flat worms (Platyhelminthes..

Eucoelomata In Eucoelomata a true body cavity is present. It is called coelom. It is a body cavity which is lined by mesoderm (or coelomic epithelium). This condition is seen in the remaining group of animals from annelids to vertebrates. fig. 10.2 - Diagrams to Show Acoelomate, Pseudocoeloma..

The male reproductive system comprises of a pair of testes that are present in a thin-walled sac called the scrotum . The scrotum is contained within the abdominal cavity in the embryonic stage. Shortly before birth, they come down and remain outside throughout life. This is because t..

a pair of , organs that produce the male gametes i.e., sperm..

Cell and Cell Structure - The cells that make up our body are so small that you would fit over 200 of them on the full stop at the end of this sentenc..

Bio - war refers to biological war. It means that biological organisms are used as weapons to carry out the war. It is latest form of war. It is carried out by spreading the pathogens in specific part of geographical region to deliberately spread a deadly disease. The ..

Due to bioaccumulative characters, these pollutants pass through the food chain and food web. While passing through the organisms, the concentration of pollutants gets increased. This is called bio magnifications. For e.g., 0.5 ppm DDT in grasses gets magnified to 2ppm in sheep. It may b..

Bio piracy refers to unauthorised and unlawful access to biological secret and use of such secrets for specific gain. In biological research many secrets have been unravelled. Genetic structures of potentially useful organisms, genetic structures of dangerous mutants o..

Bio-patent - Patenting was considered exclusively in industrial domain. Inventions, production processes were patented since long. But recently patenting is extended to biological field too. Bio-patent is the result of TRIPS (Trade related intellectual property right) ..

Patenting was considered exclusively in industrial domain. Inventions, production processes were patented since long. But recently patenting is extended to biological field too. Bio-patent is the result of TRIPS (Trade related intellectual property right) as a part of WTO agreem..