The subject of observation and experiment is biology.
An important part of teaching is also worth mentioning.
Effective means to improve the quality of biology teaching.
I have guided my study in many years of teaching practice.
The students began to make some small biomarkers.
Ben, such as butterflies, moths and pigeons.
Such as ecological specimens, can not only exercise and cultivate.
Students' practical ability can improve teaching.
Learning conditions help to stimulate students' learning.
Interest in biology class and improving teaching quality
Quantity.
Recently, I led my students to do three.
An ecological specimen of a rabbit was peeled off for teaching.
Learn to use it. Stripping specimens is taking animals.
Peel off the skin together with the covering outside the skin.
1 Sun Li Hong Ying Hou Yan Jie
Come on, then sew it into its original shape according to the prototype of the animal.
Specimens with similar living conditions are difficult and important.
There are three processes in the production process, as follows:
one
Prepare preservative and mix arsenic soap.
cream
Use100g arsenic, 300g soap and camphor.
Brain powder 10g. First, mash the soap and add a proper amount.
Boil water into paste, cool and add arsenic.
Powder, stir evenly, and finally add camphor powder to wait.
Use.
Second, peel off the specimen
1. Kill the rabbit. Inject air into carotid artery
Kill rabbits together.
2. Clean the sample. If there is blood pollution, use
Wet cotton with a little cold water and carefully dry the blood stains.
Net. Then sprinkle talcum powder on the washing place and suck it off.
Moisture dries the fur.
3. Measurement records. Measure body parts.
Length and circumference (body length, tail length, hind foot length, waist circumference)
Girth, bust, neck girth), and record the data.
As a reference for specimen repair and filling.
4. Peel the specimen. Turn the rabbit's head towards the left abdomen.
Put it face up on the experimental table, starting from the chest midline.
Split your hair and cut the skin longitudinally backward until you reach the anus.
Don't cut the skin too deep to see the muscles.
Stop, don't cut muscles or abdominal cavity to prevent internal organs.
Blood pollutes fur. Then continue to put the sides of the abdomen,
The muscles of the back and hind legs are separated from the skin.
Cut from the proximal femur, then cut the genitals, straight
Cut off the connection between the intestine and the skin and remove the root of the tail.
Connective tissue, gently rub the tail with your hand to make the skin
Relax your muscles, then hold the tail root with one hand and the other.
Hold the tail root with thumb and forefinger in one hand, and then use it.
Pull out the coccyx by force (if you can't hold it with your hands, you can use it.
Clamp it with pliers and pull it lightly to avoid breaking it). Peeling head
Pay special attention to the peeling of eyes and ears.
Never cut the skin, carefully close the eyelids and eyes.
The ball separated and the mandible peeled off to the edge of the lower lip.
Cut off the cervical vertebra outside the occipital bone, and be careful of the front and rear limbs.
Peel off the muscles at the bottom of the phalanx (leaving the toes)
Bone, convenient for ecological plastic surgery), attached to the skin.
Get rid of fat and muscle, turn around and limbs.
Remove muscles, remove tissues such as eyes, tongue and brain.
Prevent decay).
5. Apply preservatives. Apply evenly, especially.
Apply more in the cranial cavity and pay attention as much as possible.
Don't touch the dirty hair. Coating process and stripping
In this process, you should put it on the edge of the fur.
Fat cotton to avoid blood and preservative pollution.
wave
Third, filling
Preserved leather sheets should be
Fill and make specimens in time. first
First, make an iron with 12 iron wire according to the measured data.
Silk skeleton of head, spine and limbs.
Three lines (left forelimb and right hind limb,
The right forelimb is connected with the left hind limb and the head is connected with the spine.
: one at each end), each department should design it well.
The ratio of the length of points, three screwed into one.
, designed according to a good ecological attitude.
State, fixed with thin iron wire, wrapped in cotton.
All right, neck, chest and abdomen are all measured.
Stuffing (too fat and too thin to look good),
Finally, the fur is put on the prosthesis for suture and fixation.
When sewing, the needle should go from skin to skin, and the thread should be gently pulled.
In case of skin tearing. After sewing, setting and inlaying.
Instrument eye (embedded from one side and then leveled), ear
The flowers are clamped on the hard paper roll with paper tubes and fastened with large stitches.
Fixing, drying, and removing the hard paper.
The filling process must be very careful, otherwise it will affect the standard.
This quality and beauty.