Difference Between in vitro and in vivo

Main Difference – in vitro vs in vivo

In vitro, in vivo, and in silico are the three types of experimental models used in biological science laboratories. The main difference between in vitro and in vivo is that in vitro refers to the experimental procedures performed outside a living organism whereas in vivo refers to the experimental procedures performed within a living organism. In silico refers to the experiments performed on the computer. In vivo experiments are performed under physiological conditions while in vitro experiments are performed under controlled laboratory conditions.

Key Areas Covered

1. What is in vitro
– Definition, Facts, Examples
2. What is in vivo
– Definition, Facts, Examples
3. What are the Similarities Between in vitro and in vivo
– Outline of Common Features
4. What is the Difference Between in vitro and in vivo
– Comparison of Key Differences

Key Terms: Experimental Models, In vitro, In silico, In vivo, Laboratory Conditions, Physiological Conditions

What is in vitro

In vitro refers to a phenomenon in which a given procedure is performed in a controlled environment outside of a living organism. The majority of cellular experiments are performed in vitro as it is less expensive. But, the regeneration of the physiological conditions of an organism is difficult inside a test tube. Therefore, the results of the in vitro experiments are less precise. This means the results of in vitro experiments do not correspond to the circumstances occurring around living organisms. A bacterial culture is shown in figure 1.

Figure 1: Bacterial Culture

In vitro experiments are performed using the extracted cellular components from their regular biological environments. The cellular components can be microorganisms, cells, organelles or biological molecules. The cells and microorganisms are grown in artificial culture media while biological molecules are studied in solutions. The in vitro experiments are performed in Petri dishes, test tubes or flasks.

What is in vivo

In vivo refers to a phenomenon in which experiments are performed using a whole, living organism. The two forms of in vivo experiments are animal studies and clinical trials during drug development. The overall effect of the experiment on a living organism can be observed in in vivo techniques. Thus, in vivo experiments are more precise than in vitro experiments. The main objective of in vivo experiments is to gain knowledge about biological systems or discover drugs. A lab mouse is shown in figure 2.

Figure 2: Lab Mouse

However, in vivo experiments are more expensive and require more advanced techniques during the experiment. Mice, rabbit, and apes are the three main types of living organisms used in in vivo techniques.

Similarities Between in vitro and in vivo

In vitro and in vivo are two types of experimental models used in laboratories.
Both in vitro and in vivo experiments are performed under a given set of conditions.
Fertilization can be performed in both in vitro and in vivo

Definition

In vitro: In vitro refers to a phenomenon in which a given procedure is performed in a controlled environment outside of a living organism.

In vivo: In vivo refers to a phenomenon in which experiments are performed using a whole, living organism.

Types of Samples

In vitro: Dead organisms or isolated cellular components are used in in vitro experiments.

In vivo: A whole living organism is used in in vivo experiments.

Conditions

In vitro: In vitro experiments are performed under controlled laboratory conditions.

In vivo: In vivo experiments are performed under physiological conditions.

Cost

In vitro: In vitro experiments are less expensive.

In vivo: In vivo experiments are expensive.

Time

In vitro: In vitro experiments are less time-consuming.

In vivo: In vivo experiments are more time-consuming.

Presicion

In vitro: In vitro experiments are less precise.

In vivo: In vivo experiments are more precise.

Examples

In vitro: Cell culture experiments in Petri dishes and experiments in test tubes are examples of in vitro.

In vivo: Drug testing experiments performed by using model organisms such as mice, rabbit, apes etc. are examples.

Fertilization

In vitro: In vitro fertilization (IVF) refers to the artificial fertilization method in which fusion of male and female gametes occurs outside the human body.

In vivo: Regular fertilization mechanism in which the fusion of male and female gametes occurs within the body is referred to as in vivo fertilization.

Conclusion

In vitro and in vivo are two types of experimental methods used in laboratories. In vitro experiments are performed in test tubes. These experiments are performed under laboratory conditions. But, in vivo experiments are performed within living organisms. These experiments take place under physiological conditions. The main difference between in vitro and in vivo is the type of conditions under which each type of experiments are performed.

Reference:

1. Pearson, R M. “In-Vitro techniques: can they replace animal testing?” Human reproduction (Oxford, England)., U.S. National Library of Medicine, Dec. 1986, Available here.
2.“In vivo.” Wikipedia, Wikimedia Foundation, 11 Jan. 2018, Available here.

Image Courtesy:

1. “Bacterial culture” By Joydeep – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Lab mouse mg 3213” By Rama – Own work (CC BY-SA 2.0 fr) via Commons Wikimedia