The correct answer i think is antibodies
Permafrost layer in Tundra is the layer of earth beneath the topsoil that remains frozen during the year and is usually only a few feet beneath the surface. It prevents trees from growing in the tundra because trees need to have deeper roots plus they cannot grow in the frozen ground.
Biome plants are : shrubs, sedges, mosses, lichens, grasses, and some flowering or herbaceous plants.
Answer:
Defective checkpoints results in death of the cell.
Normal checkpoints make sure the cell has enough resources for cell division. Normal checkpoints ensure the cells commits apoptosis if the cell has a problem it cannot fix itself.
The concept would be crystallization. As magma cools inside or outside of the earth it crystallizes into an igneous rock. Intrusive (formed inside crust) igneous rocks are typically more course grained and contain many different noticeable minerals (for example, granite). Extrusive (formed outside) igneous rocks are typically more porous and are more fine grained then intrusive rocks (example, obsidian).
