12/27 - Laboratory Techniques

Front

What is a restriction enzyme?

Back

A restriction enzyme is a protein that cuts DNA at specific sequences, known as recognition sites, allowing for DNA manipulation in molecular biology.

Front

What is column chromatography?

Back

Column chromatography is a laboratory technique used to separate mixtures based on the differential affinities of compounds to the stationary phase (e.g., glass beads) and the mobile phase.

Front

What does it mean for a compound to be polar?

Back

A polar compound has a distribution of electrical charge that leads to the formation of positive and negative poles, resulting in interactions with other polar substances.

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What is isoelectric focusing?

Back

Isoelectric focusing is a technique used to separate proteins based on their isoelectric point (pI), where proteins migrate in a pH gradient until they reach a point where their net charge is zero.

Front

What is the significance of a protein's isoelectric point (pI)?

Back

The isoelectric point (pI) is the pH at which a protein has no net charge, affecting its solubility and interaction with other molecules.

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What is UV-Vis spectrometry used for?

Back

UV-Vis spectrometry is used to analyze the absorbance of UV and visible light by a sample, helping to identify the presence of conjugated pi systems and functional groups.

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What is the difference between simple and fractional distillation?

Back

Simple distillation is used for separating liquids with significantly different boiling points (usually >25°C), while fractional distillation is used for separating liquids with closer boiling points (typically <25°C).

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What is vacuum distillation?

Back

Vacuum distillation is a technique that lowers the boiling point of liquids by reducing the pressure, allowing for the separation of heat-sensitive compounds.

Front

What are conjugated pi systems?

Back

Conjugated pi systems are structures in organic molecules where alternating single and double bonds allow for delocalization of electrons, affecting their optical properties.

Front

What is the role of glass beads in column chromatography?

Back

Glass beads in column chromatography serve as the stationary phase, providing a surface for the separation of compounds based on their polarity.