Pipetting Techniques Quiz

_______ Permit the transfer of accurately known volumes from one container to another.

A volumetric, or transfer, pipet delivers a single, fixed volume between 0.5 and 200 Ml. Measuring Pipets are calibrated in convenient units to permit delivery of any volume up to a maximum capacity ranging from 0.1 to 25 Ml.

Transfer small quantities of liquids. Plastic bulb pipettes are typically not precise enough to be used for exact measurements but their glass counterparts can be extremely precise. The longer and thinner the tip of a glass pipette is the more exact the measurement.

Have a plain, narrow tube which extends to a tip and graduates uniformly along its length. With a Mohr pipette, calibration marks may be confined to the stem.

______ College Medical Technology Department City of Koronadal, South Cotabato

Air displacement is a fundamental principle that underlies the functioning of many types of ______

When the plunger of the pipette is depressed to its first stop, a partial vacuum is created within the pipette's chamber above the ______

When the pipette is positioned over the target container, the plunger is further depressed to the second stop, expelling the liquid from the tip and into the target ______

Volumetric pipettes offer very accurate volume measurement of a solution. They have a large bulb with a long narrow portion. This portion has a single graduation mark, as it is calibrated for a single volume such as 10, 25, and 50 mL. These pipettes are commonly used in analytical chemistry to make laboratory solutions from a base stock as well as prepare solutions for ______.

Single channel vs. multichannel pipettes are determined based on the total number of pistons in the pipette. For manual high-throughput lab applications, most would prefer a multichannel pipette instead of a single channel, which would require filling well by well. These pipettes are used for precise measurement of volume and dispensation in ______.

Electronic pipettes were developed to improve ergonomics by reducing the necessary force. The manual movement of the piston is replaced by a small battery-powered electric motor. Whereas manual pipettes need a movement of the thumb (up to 3 cm), electronic pipettes use a main ______.

With a serologic pipette, they may extend to the tip. These pipettes operate on the principle of air displacement. Aspiration in pipetting is a critical step when working with ______ specimens.