In most companies, they're just different names for the same role. They're all typically the person who either does outbound calling for an account rep or who answers inbound leads, filtering them for an account rep. The typical progression is the following: BDR, SDR, LDR - development rep. Answers inbound leads, makes outbound calls, generates new opportunities for a rep. Sales Rep, Account Rep, Account Executive - salesperson. does the actual selling, builds longer term relationships, closes deals.
The plasma membrane is the outer lining of the cell. It separates the cell from its environment and allows materials to enter and leave the cell. Ribosomes. Ribosomes are organelles that process the cellâs genetic instructions to create proteins.
However, if cells do need to use energy to get particles through the cell membrane this is called active transport. Passive transport Passive transport: diffusion. Some substances pass through small holes in the surface cell membrane. This is called diffusion and does not require the cell to expend energy. Oxygen gets into a cell and carbon dioxide (the product of respiration reactions) leaves it this way.