Answer: The correct answer for the fill in the blank is osmosis.
Osmosis is defined as the movement of solvent (like water) from a region where the concentration of solute is lower to a region where the concentration of solute is higher though a semipermeable membrane.
In other words, it is the water movement from an area where its ( water ) concentration is higher to an area where its concentration is lower.
This process does not require any energy as water is moving along the concentration gradient.
Answer - Ground water erosion is a type of carbonic acidic water. That goes into the holes thru the soil and pretty much cracks thru rocks.
Depending on the structure of cells (shapes and organelles) we can differentiate cells and therefore create different groups and classifications based on their differences and functions.
The eukaryote-prokaryote division bases itself on the possesion of a nucleus that creates a boundary for the genetic materifal. In this case, eukaryotes have it while prokaryotes don't.
Hope it helped,
BiologiaMagister
