What membrane transport mechanism is used to return calcium ions to the er and what membrane protein would be used.

Molecular Transport - Proteins are used to move small molecules such as calcium, potassium, and sodium ions across the membrane. - cell takes in large particles by engulfing them. Phagocytosis - "cell eating" - extensions off cytoplasm surround a particle and package it within a food vacuole and then the cell engulfs it.