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
Transport of molecules in simple diffusion is not determined by: 
Select and explain. 
A. ATP usage, B. Size of molecule, C. Lipid solubility, D. Number of channels
A: ATP usage
Answer: A: ATP usage 
Explanation: Ref: Pal GK. Transport across Cel! membrane. In: Textbook of medical physiology. 2""' ed. Abuja publishing house. 2011: 4: 32,33.Explanation:Permeability of substances across the membrane is decided by1. Lipid - solubility2. Molecular size3. Charge of the molecule4. Temperature5. Distribution of channels in the membrane6. Pressure gradientSimple and passive diffusion are passive transport and energy is not do not require utilization of metabolic energy (ATP)