<span>Human genetic disorders can be caused largely by the change of the DNA sequence from its normal sequence. This can also be caused by a monogenic disorder, a mutation in a gene. So the best answer to this question would be letter B since nondisjunction causes chromosomal abnormalities.</span>
Answer:
d. nitrogen-containing base
.
Explanation:
A nucleotide comprises a phosphate group, a pentose sugar and a nitrogenous base (nitrogen-containing base).
A nitrogenous base is a type of aromatic heterocyclic organic compound which essentially has nitrogen in it. The base can be a purine or pyrimidine. Purine nitrogenous bases are adenine (A) and guanine (G) while pyrimidine nitrogenous bases are cytosine (C), thiamine (T) and uracil (U).
Till the time a base is not attached to covalently linked phosphate group and a pentose sugar, it is known as nucleoside. But as soon as we attach any nitrogenous base to the nucleoside, a nucleotide is formed. So it means a nucleotide is nucleoside + nitrogenous base.
Examples are as under:
A nucleotide which has adenine as nitrogenous base is known as adenosine triphosphate (ATP) while a nucleotide which has guanine as nitrogenous base is known as Guanosine-5'-triphosphate (GTP).
Transform boundary – this type of fault is found where two tectonic plates are moving alongside and parallel to each other mostly in opposite directions. This type of fault is also responsible for the rift valley and block mountains. No crust is destroyed nor new crust formed.
Convergent boundary – At this point, two tectonic plates are colliding because they are moving in opposite directions at each other. The pressure and stress of the collision force causes the plates to begin crumpling and folding at the boundary forming features such as fold mountains (an example is the Himalayas).
Convergent boundary – At this boundary , the denser of the two colliding tectonic plates (usually the oceanic plate) is subsided by the less dense one (usually the continental plate). The plate being subsided begins to melt as it does down into the mantle and becomes liquid rock. This magma rises through the fissures formed at the boundary and erupts into volcanic islands along the boundary.