Primary succession occurs on basically empty, lifeless land with no soil. Pioneer species are the first plants to colonize the land after primary succession, which means they are very primitive and can survive without soil. Since there is no soil, their role is to create soil for more advanced organisms to survive in the area in the future.
Pioneer species refers to the first species that colonize the area and serves as first stage of succession. Pioneer species initiate the soil formation by breakdown of substratum.
Example: Crustose lichens are pioneer species on rock surface. These species carry out rock erosion to initiate soil formation. Addition of dead and decayed lichen to the soil makes it fertile and suitable for growth of other plant species.
A dominant part of aquatic animals like fish and prawns inhale through uncommon organs called gills.
The skin that help in utilizing oxygen broke up in water. which help in return of gases and Gills contain veins.
Amphibian life forms have a unique organ called gills, which permits them to inhale oxygen in the water.
The two sides of the pharynx (throat) by the Gills when the gases exchange in fish .
<em>Gills are tissues that resemble short strings, protein structures called fibers. </em>
These fibers have numerous capacities including the exchange of particles and water, just as the trading of <em>oxygen, carbon dioxide, acids and alkali.</em>
Prokaryotic cells do not have membrane bound organelles. Eukaryotic cells do have membrane bound organelles. The membrane controls movement in and out of the cell. ... The cytoplasm fills the space between the nucleus and the cell membrane.
