The answer that fits the given blank above is MIDBRAIN. The MIDBRAIN is in the deep areas of the brain and includes the parts such as the substantia nigra, reticular formation and the ventral tegmental area. The midbrain is responsible for hearing, vision, sleep/wake, arousal, motor control and the regulation of temperature.
<h2>The correct answer is Facilitated Diffusion.</h2>
Explanation:
Facilitated Diffusion can be defined as the mechanism by which molecules are made to translocate from a region where their concentration is high to a region where their concentration is low through an integral membrane protein that spans the plasma membrane forming a channel across the membrane connecting the cell interior with the cell exterior.
Here, as the molecules move along or down their concentration gradient so no expenditure of energy in the form of ATP or Adenosine Triphosphate occurs.
Polar molecules like glucose form hydrogen bonds with water molecules. They are not allowed to diffuse directly across the lipid bilayer because the lipid bilayer is hydrophobic and avoid water molecules and also polar molecules.
Hence, the glucose molecules need to get transported through protein channels that span the lipid bilayer of the plasma membrane.
These proteins have amphipathic nature, that is, they are composed of both polar and non-polar amino acid residues. The non-polar residues face towards the lipid molecules in the membrane and form hydrophobic interactions with them while the polar residues face the lumen of the channel and form hydrogen bonds with the polar molecules those are translocated across the membrane.
Plants respire all the time, whether it is dark or light, because their cells need energy to stay alive. But they can only photosynthesize when they have light.