This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Physiology
Placenta to fetus glucose is transported by: 
Select and explain. 
A. Endocytosis, B. Active transport, C. Facilitated diffusion, D. Simple diffusion
C: Facilitated diffusion
Answer: C: Facilitated diffusion 
Explanation: Ans. C Facilitated diffusionRef. Quantitative Human Physiology; An Introduction, pg. 126-27Since the transport of glucose to placenta is via GLUT, it is called a facilitated transfer of glucose. Simple diffusionFacilitated diffusionEnergyNot requiredNot requiredCarrier moleculeNot involvedInvolvedSaturationNot saturable (No Tm)Saturable (has a Tm)FollowsFick's law of diffusionEnzyme-substrate kinetics of Michaelis mentenExample:O2 and CO2 exchange in alveoliGlucose transport by glucose transporters (GLUT)