Answer: D) Polygenic
Explanation: Polygenic inheritance describes the inheritance of traits that are determined by more than one gene. These genes, called polygenes, produce specific traits when they are expressed together. Polygenic traits have many possible phenotypes (physical characteristics) that are determined by interactions among several alleles. Examples of polygenic inheritance in humans include traits such as skin color, eye color, hair color, body shape, height, and weight.
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.
There is no pigment in the brain, so it is in it's natural colour, grey.
