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Overview of the MFD005a chip and components A. Overview of the MFD005a chip’s architecture. Flow directions in each segment during running conditions are given by black arrows, during loading conditions by white arrows. Note that only flow from ports 4, 5 and across the cell chamber changes direction during loading. Letters represent locations of the features described in other parts of the figure. External ports are numbered 1-5. Each port is described in Table IV. B. Depiction of the DAW junction. Flow direction is indicated by the black arrows. The two inlets on the right come from ports 1 and 2. The flow from the inlets converges in a ratio dependent on the inlet pressures of each. The middle fork of the junction leads to the cell chamber while the two outer forks lead to port 3, the cell and shunt waste port. C. Depiction of the staggered herringbone mixers (SHM) which reduce the channel length required for mixing. These mixers immediately follow the DAW junction and continue until just before the cell chamber. D. Overview of trap region of the MFD005a chip under loading conditions. This trap is known as the yeast doughnut trap. Black region represents the cell chamber with a height of 10 µm. Gray region is the actual cell trap, with a height of 3.525 µm. White circles represent cells entering from the cell port and either passing around the trap to the cell and shunt waste (port 3), or entering the central channel and moving to the trap entry barrier. The yeast cells are slightly too large to move into the trap directly without “flicking” the cell line to assist in their entry. E. Cell trap upon running of an experiment. Cells begin to grow in the trap and the colony expands (black arrows). Eventually the colony fills up the gray region near where they were loaded. The growth of the cells will force some out of the trap into the outer channel where they will be efficiently carried away to the waste port (white arrows). Over the course of the experiment the cell colony will expand to fill the entire trap.