← New search

Other meanings of Biological specimen

Life Sciences

Biological specimen

A biological specimen is a sample of biological material—such as tissue, blood, urine, plant parts, or microorganisms—collected for analysis, research, or diagnostic purposes. Specimens are essential in fields like medicine, ecology, and taxonomy, enabling scientists to study structure, function, and disease. They are often preserved, stored, and cataloged in biobanks or natural history collections, forming the basis for countless discoveries.

~10^8
Estimated specimens in the Smithsonian's National Museum of Natural History
Collection size
~70%
Proportion of human tissue samples in biobanks used for research (approximate)
Research use
~4°C
Typical short-term storage temperature for fresh specimens
Storage temperature
1

Definition and types

A biological specimen is any sample of biological material collected for examination. Common types include blood, urine, saliva, tissue biopsies, plant specimens, and microbial cultures. Specimens can be classified as clinical (for medical diagnosis) or research (for scientific study). They may be obtained from living organisms, such as blood draws, or from dead organisms, such as herbarium sheets. The choice of specimen type depends on the research question or diagnostic need.

2

Collection and preservation

Proper collection and preservation are critical to maintain specimen integrity. Methods vary: blood is collected in anticoagulant tubes, tissues are fixed in formalin, and plant specimens are pressed and dried. For long-term storage, specimens may be frozen at -80°C or in liquid nitrogen, or embedded in paraffin. Biobanks follow strict protocols to ensure quality and traceability, often using barcoding and standardized metadata.

3

Applications

Biological specimens underpin medical diagnostics, drug development, and environmental monitoring. In clinical settings, specimens are used for laboratory tests that detect diseases like diabetes or cancer. In research, they enable genomic sequencing and biomarker discovery. Natural history collections preserve specimens for taxonomic and evolutionary studies, providing a historical record of biodiversity. Specimens also support forensic science, agriculture, and conservation biology.

4

Lesser-known aspects

Beyond the familiar uses, biological specimens have surprising applications. For instance, herbarium specimens have been used to track historical pollution levels and the spread of plant pathogens. Frozen tissue samples from zoos contribute to genetic rescue efforts for endangered species. In forensics, insect specimens on corpses help estimate time of death. Additionally, the field of specimenomics uses museum collections to study DNA degradation over time, informing ancient DNA research.

Glossary

Biobank
A facility that stores biological specimens for research.
Herbarium
A collection of preserved plant specimens used for scientific study.
Fixative
A chemical, such as formalin, used to preserve tissue structure.

Specimens are the foundation of biological knowledge, bridging the gap between field and laboratory.