A Look inside the Lab

The Next Step Science “A Look inside the Lab” series is comprised of short videos and novel reading passages designed to introduce students to commonly used laboratory equipment and the scientists who use it. The series can be used to enhance an existing lesson or as a starting point for introducing a concept. 

We would like to thank our colleagues at the Children's Hospital of Philadelphia Research Institute, who allowed us to join them in their labs to film the video series. We also thank the individual scientists who generously shared their time and expertise in the interviews.  

Liquid Nitrogen Freezer  

The liquid nitrogen freezer stores items at -210 degrees Celsius. This type of freezer is used for cryopreservation of cells and tissue. It is also used for certain vaccines that require low-temperature storage for product stability.


Scientists use different types of microscopes in the laboratory. Different features and magnification capabilities enable scientists to choose the best option for the experiments that they are doing. Microscopes have been instrumental for studying and learning about cells, pathogens and other items too small to be seen with the naked eye. 

Gel Electrophoresis 

Gel electrophoresis is a process used to separate biological molecules, like DNA or proteins, based on molecular size and electric charge. The process of gel electrophoresis has many applications in the laboratory. For example, it can be used to detect pathogens, diagnose genetic disorders, or aid with DNA fingerprinting. 


Polymerase chain reaction, also known as PCR, is a laboratory technique that models DNA replication, allowing scientists to synthesize DNA. PCR can rapidly generate millions of copies of a specific DNA sample, so small samples of DNA can be used for analysis or experimentation. PCR has many applications, including molecular biology research, forensic identification, and medical testing.