both ethanol and glycine are small molecules of approximately equal molecular weight. However, ethanol is much more membrane permeable than glycine. What accounts for the large difference in membrane permeability between ethanol and glycine

Ethanol is a non polar molecule.Therefore it passes through the cells membrane easily by diffusion like other non polar like CO2 and water.However, glycine is an amino acid ( the simplest amino acid) a charged molecule /polar molecule/.it can not therefore pass through the bilayer by simple diffusion because of the phospholipid bi-layers. Therefore special transport proteins are needed for its passage across the cell membrane.

Example-GLYT 1 and 2 are the carrier proteins  specific for glycine transport across the membrane.

G

Explanation:

propane is burned to provide the heat in many cooking grills. the chemical reaction for this process is shown in the equation below.

c3h8 + 5o2 ? 3 co2 + 4h2o + energy

what are the products in this chemical reaction?

3co2 + 4h2o + energy