Answer:
Sea floor spreading-> <u><em>Oceanic ridge and Magma pushing two plates apart</em></u>
Continental drift-> <u><em>Concept of pangaea and Oceanic plates sliding under continental crust</em></u>
Explanation:
Due to the divergent plate movement, the magma come out to the surface, forming the mid oceanic ridge and this separation of plates on the sea floor is known as the sea floor spreading. The magma here pushes the two plates to move apart because of the convection current that generates in the mantle. One example of mid oceanic ridge is the Mid-Atlantic Ridge.
Continental drift refers to the slow and gradual movement of the lithospheric plates over the viscous asthenosphere layer. This motion of continents takes place because of the plate tectonic movement. Due to this plate motion, the denser plate gets subducts beneath the less denser plates. For example, the oceanic crust when collides with a continental crust, it gets subducted because of its higher density. The great supercontinent "pangaea" also formed and separated due to this plate motion.
Lignin
It is a complex organic polymer that form an important structural materials in the support system of vascular plants and can also be found in some algae. This is an important molecule in the structural composition of cell wall, such as in wood and bark. This also allow woods and barks to have strong, rigid which allows them to no break easily. Lignin can also be found inserted in the cell wall of this plants.
Answer:
It is the arrangement of nucleotide within the genes which differs among DNA structures of different species. Each gene contains several codons which is three nucleotide long
One reason would be the increased chance of Down syndrome