Open Field Tests

A line drawing of two mice walking similar paths, but one is curvy because that mouse is woozy. Understanding or measuring how animals think is difficult when they can’t talk to you. You can’t ask ‘what are you feeling?‘ much less, ‘why do you feel that way?‘, but it is still important to understand. For instance, we study drugs to all kinds of psychological issues (depression, alzheimer’s, Parkinson’s disease, etc) in rodents like mice and rats. Therefore, biologists have developed behavioral tests that inform us about what the animal is thinking or feeling.

The open field test measures general activity level and exploration behaviors. This lets us get a feel for how the animal behaves normally and is frequently used as a control in an experiment. In addition, numerous factors can influence how much an animal moves so by controlling what changes between tests, we can begin to understand how what we are testing influences the animal’s thinking.

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In situs

In situ hybridization (ISH) is a technique that allow you to visualize a gene’s location. The location is typically determined at the level of the cell or tissue region. However, chromosome painting is also a form of in situ and has a better resolution. In general, if a scientist is talking about ‘in situs’ or WISH, they are referring to the form that shows where a gene is being expressed.

In situ hybridization is like a Google search, where the probe is our search term.

At the most basic …

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PCR - Photocopying Genes

PCR is a common technique used to amplify specific regions of DNA. Put more simply, its a process that allows us to create copies of a piece of DNA. There are two main properties of PCR that we take advantage of - amplification (getting many copies) and isolation (of a single region).

If you understand the basic idea of photocopying, then you can understand PCR.

A short stretch of DNA that goes through 2 cycles of amplification ending up with 4 copies. I should note that the role of PCR has changed over time and I will mostly be focusing on the current use. Additionally, there are several …

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Gene Cloning: vectors, plasmids, ligations, and transformation - oh my!

The goal of gene cloning is to get a single copy of the gene from an animal and into an archive. The rest is just the individual steps necessary to do this. Cloning genes allows us to easily and consistently retrieve the exact same copy and to share it between labs or even organisms.

Step Description Biology Jargon
1     Get a copy of the gene from the animal PCR
2     Put the gene in an archival format Ligation into a plasmid
3     Make backup copies or archive it Bacterial transformation …
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