Answer:
"rubbed together"
Explanation:
Friction is the resistance to motion of one object moving relative to another. It is not a fundamental force, like gravity or electromagnetism. Instead, scientists believe it is the result of the electromagnetic attraction between charged particles in two touching surfaces.
B. usually contains a large amount of matrix
Answer:
availability of resources.
Explanation:
Availability of resources is abiotic factor which is responsible for the decrease in population in 1990 because when the population reaches its carrying capacity so the organisms compete with each other and due to limited resources such as food etc the decrease occurs in population. Infection is also occurs when there is high population due to which death occurs and population of organism decreases.
The hydrogen bonding of nucleotides into a new DNA molecule is facilitated by enzymes. Hydrogen bonding is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. The nucleotides in a base pair are complementary which means their shape allows them to bond together with hydrogen bonds. The A-T pairs forms two hydrogen bonds while the C-G pair forms three. The enzymes called DNA polymerases join the nucleotides by way of phosphodiester bonds.