Around 40 weeks is when it occurs
The 2 major components or parts that compose or make up the plasma membrane of a eukaryotic cell would be the phospholipids arranged as a bilayer, having phospholipids arranged side by side in an upright and inverted manner, allowing for the hydrophobic and hydrophilic regions to interact respectively, and also Protein molecules, more specifically Transmembrane Proteins and Integral Proteins.