specimen
Definition
A specimen is a single example of something. It can be a living organism, a plant, an animal, a rock, or any other object that is studied by scientists.
Specimens are important for scientific research because they provide scientists with physical evidence to study. They can also be used to teach people about different organisms and objects.
There are many different types of specimens, each with its own advantages and disadvantages. For example, living specimens can be used to study the behaviour and physiology of organisms, but they can be difficult to maintain in captivity. Fossil specimens can be used to study the evolution of organisms, but they can be rare and difficult to find.
Specimens are often preserved in a variety of ways to prevent them from decaying. They can be dried, frozen, or stored in alcohol. They can also be embedded in resin or mounted on slides.
The preservation method used depends on the type of specimen and the purpose of the study. For example, a plant specimen that is to be studied for its anatomy might be preserved in alcohol, while a fossil specimen that is to be studied for its age might be embedded in resin.
Specimens are an essential tool for scientific research. They provide scientists with physical evidence to study and help them to learn more about the natural world.
How can the word be used?
The museum has a large collection of dinosaur specimens.
Different forms of the word
Noun: specimen (plural: specimens).
Adjective: specious.
Verb: to specimenise.
Etymology
The word "specimen" comes from the Latin word "specimin", which means "sample" or "example". It was first used in English in the 16th century to refer to a sample of something, such as a plant or an animal.
The word "specious" means "superficially attractive but lacking in substance". It comes from the same Latin root as "specimen".
The word "to specimenize" means "to collect or examine specimens". It is a relatively new word, first used in the 19th century.
Question
What is a specimen?
AQA Science Exam Question and Answer
Question:
Explain the process of preserving and preparing biological specimens for microscopic observation. Include the key steps involved and the importance of each step in maintaining specimen integrity.
Answer:
Preserving and preparing biological specimens for microscopic observation is a crucial process in scientific research and education. It ensures that the specimens retain their structural integrity and allow accurate study under the microscope. The key steps involved in this process are fixation, dehydration, clearing, embedding, sectioning, staining, and mounting.
Fixation involves immersing the specimen in a fixative solution like formaldehyde, which halts decay by cross-linking proteins and preserving cellular structures. Dehydration follows, gradually replacing water with alcohol to prevent shrinkage during subsequent steps. Clearing removes alcohol and ensures transparency using substances like xylene, allowing better light penetration during microscopy.
Embedding includes encasing the specimen in a solid medium like paraffin, providing support for sectioning. Thin sections are then obtained using a microtome, enabling detailed examination. Staining enhances the visibility of specific structures, highlighting features of interest. Finally, mounting secures the stained specimen on a slide with a coverslip and a mounting medium, preventing distortion and facilitating easy observation.
Each step plays a crucial role in maintaining the integrity of the specimen, ensuring an accurate representation of cellular structures and facilitating insightful microscopic examination.