AP BIOLOGY

Detailed explanation-1: -Lava from a volcanic eruption hardens into bare rock. Primary succession begins with soil formation. The first stage of succession involves pioneer species. In primary succession, pioneer plants are those that can grow without soil, such as lichens.

Detailed explanation-2: -This process is called primary succession. It begins with organisms such as lichens that can live and grow very slowly on bare rock. Lichens (see the Fungi station) break down rock by secreting acids.

Detailed explanation-3: -Primary succession begins with the appearance of pioneer species – lichen, mosses, and fungi – all organisms that can grow on rocks and exposed land. These are small, simple organisms that can survive harsh conditions, fix inorganic carbon and nitrogen into usable nutrients and accelerate the process of weathering.

Detailed explanation-4: -2 Most primary succession begins with lichens. Acids from the lichens begin breaking the rocks into small particles. These particles mix with the remains of dead lichens to start forming soil. Because lichens are the first organisms to live on the rock, they are called pioneer species.

Detailed explanation-5: -Secondary succession occurs when the starting point is bare soil that already exists. It is similar to primary succession, however, the pioneer species are often fast-growing plants and often come from pre-existing groups of organisms in the area.