The hydrophobic domain consists of one, multiple, or a combination of -helices and sheet protein motifs.
Most of the biological molecules are either larger in size or having definite charges on it. Hence The plasma membrane is non permeable to it. lipid bilayer is permeable only to water molecules and a few other small, uncharged, molecules like oxygen (O2) and carbon dioxide (CO2). These diffuse freely in and out of the cell.
Passive transport involves carriers, channels, or direct diffusion through a membrane. This type of transport always operates from regions of greater concentration to regions of lesser concentration. No external source of energy is required, thus "passive" whereas in In active transport it is possible to go against the concentration gradient and an external source of energy like ATP is required to move the carrier and its materials thus, "active"
G1 phase: The first phase within interphase, from the end of the previous M phase till the beginning of DNA synthesis is called G1 (G indicating gap or growth). ...Show more