Under what circumstances is the biospecimen registry used

Biological specimens refer to the whole or part of animals or plants after sorting, after processing, to maintain their original shape or characteristics, and stored in scientific research units, school laboratories or museums, for biology and other disciplines for scientific research, teaching or display and observation of physical objects.

Catch a small animal first, put it in the refrigerator, and you're good to go.

It is not very easy to collect and produce a qualified biological specimen, which not only needs to go through a series of processing, but also strictly follow the following 4 basic principles.

1. The principle of authenticity.

The principle of authenticity requires that the biological specimen must be a biological entity that actually exists. If a biological specimen loses its authenticity, it has no value and is meaningless. The essence of a biological specimen is the processed organism itself, so if the organism itself is not used when making a biological specimen, but something else is used instead, the "specimen" produced in this way cannot be called a biological specimen.

Different parts of different animals and plants cannot be pieced together, and it is necessary to prevent the loss of authenticity of specimens by confusing them with authenticity.

2. The principle of typicality.

Typicality means that the biological specimen collected must be the most prominent features of the species, and these characteristics must be the most obvious and telling. For this reason, it is necessary to collect those organisms with typical characteristics, which will bring many unnecessary troubles to classification, naming, identification, and identification.

3. The principle of integrity.

The principle of integrity requires that the organism used to produce biological specimens should not be missing from the east and west, but should be a complete whole. For example, a plant includes roots, stems, leaves, flowers, fruits, and seeds, and to make a complete herbal leaf specimen, these 6 parts should be intact; If the flowers are damaged, the fruit is lost, or the roots are broken during collection, the plant should not be taxidermy, and even if it does, it has lost its biological significance. Because there are stages of plant growth and development, it is usually impossible to collect the whole plant with flowers and fruits at one time, but it is necessary to collect all the plants in batches according to the flowering and fruiting stages of different types of plants.

Fourth, scientific and artistic.

It is self-evident that biological specimens should respect science in terms of production technology, naming, etc., that is, biological specimens should be scientific. But at the same time, attention should be paid to the artistry of biological specimens; Some specimens are indeed very scientific, but they are shoddy and make people look uncomfortable, which is also undesirable.

Making biological specimens is a technical operation that combines science and art. Relatively speaking, biological specimens within the scope of popular science, while emphasizing the scientificity, it is necessary to appropriately cooperate with some technological means in the production process, such as the posture of the specimens and the configuration of some brief backgrounds, as well as appropriate decoration. However, since it is a biological specimen, it should be based on science, supplemented by artistry, and some unnecessary processing and embellishment should not be played too loudly, so as not to lose the scientific application value of the specimen, that is, attention should be paid to maintaining the scientific and serious atmosphere of biological specimens.

For example, in the middle school plant specimen competition, some specimens are appropriately decorated with colored blow molding paper as a foil for the specimen, and the appearance is more coordinated and generous, but some specimens are pasted with unnecessary lace outside the foil, which takes more work, and actually destroys the seriousness of the specimen.

Take insect specimens as an example:

1. Soak the insect as a whole in hot water to be soft (don't worry about discoloration and other problems, rest assured and bold clubbing), take it out after the insect body joints become soft, generally 5-30 minutes, you can take out the insects halfway to test the softness and hardness of the insect leg joints, and advance or extend the soaking time according to the degree of softness and hardness. After it is completely soft, use absorbent paper to absorb the moisture on the surface of the insects. (Note, insects with dense hairs or scales are not suitable for soaking).

2. Take out the insect needle, prick it at the shoulder of the insect's right wing, and penetrate the body. The needle cap is 1 cm away from the body (see below for the oblique side of the insect, blue arrow). In addition, the insect needle should be kept at an angle perfectly perpendicular to the plane of the insect's body.

3. Insert the insect on the foam board so that the body is attached to the foam board. Take out the fixation stick (you can use a toothpick or insect needle) and fix the insect legs according to the principle that most insects have their forefeet forward and their middle hindfeet backwards. (The standard posture is as shown below, the more symmetrical the legs on both sides of the body, the better).

4. Take out the fixing stick (you can use a toothpick or an insect needle), and fix the insect legs according to the principle that most insects have their forefeet forward and their middle hindfeet are backwards.

5. After the insect fixation is completed, place it in a cool and dry environment for 4-5 days (the larger the insect, the more southern the area, and the longer the drying time should be.) On the contrary, if the insects are small, or in a very dry environment such as Beijing in the north, it will be fine for two or three days).

After that, gently pull out all the leg fixers, pinch the only insect needle left on the back, and carefully remove the insect from the board (note, the insect needle on the back of the insect does not need to be pulled out of the insect body!). That is a support point for specimen observation and storage. The rest of the needles and fixators are removed. ）

6. Insert the insect specimen into the specimen box, and the insect specimen production and collection is completed.

Staining is one of the most important links in the production of biological microscope slide specimens Through staining, biological tissues are immersed in a stain, so that a certain part of the tissue cell is stained with a different color or depth from other parts, and a different refractive index is produced, so that it can be observed without affecting the cell structure If the cell itself has color, it does not need to be stained

Therefore, the answer is: staining is one of the most important links in the production of biological microscope slide specimens Through staining, the biological tissue is immersed in the stain, so that a certain part of the tissue cell is dyed with a different color or a different depth from other parts, and a different refractive index is produced, so that it can be observed that it will not affect the cell structure If the cell itself has color, it does not need to be stained