Paramecium is a small, cylindrical protozoan with only one cell. It is a single-cell animal and hermaphrodite. The most common is Paramecia caudalis. The body length is only 180-280 microns. It and the amoeba have the shortest life span, measured in hours, with a life span of about one day and night. It is called Paramecium because its body shape looks like an inverted straw sole when viewed from a flat angle.
The functional division of paramecium organelles is as follows: Oral cavity (oral groove): feeding. It is estimated that a paramecium can form about 60 food bubbles per hour, and each food bubble contains about 30 food bubbles. Bacteria, therefore, a paramecium can eat about 43,000 bacteria every day, and it has a certain purification effect on sewage. Epimembrane: Oxygen intake and carbon dioxide emission are all through the epidermis. Large nucleus: Nutritional metabolism. Small nucleus: Contains genetic material, reproductive function. Food vacuole: Food vacuole is produced by endocytosis of Paramecium. After entering the cell, it will interact with Primary lysosomes fuse to form secondary lysosomes. The food vacuole flows with the cytoplasm, and the food in it is gradually digested. Telescopic bubbles and collection tubes: collect metabolic waste and excess water and discharge them outside the body. Anus: discharge indigestible food residues. Cilia: assist in movement. Paramecium rotates forward in the water by the swing of cilia
Food excretion Channel
Oral groove (food entry) - food vacuole (digestion) - anus (excretion)
Edit this paragraph's role in the ecological environment
Paramecium belongs to the most primitive and lowest protozoa in the animal kingdom. It likes to live in rice fields, ditches or ponds with little water flow, where there is a lot of organic matter, and feeds on bacteria and single-cell algae. It is estimated that a Paramecium can form about 60 food bubbles per hour, and each food bubble contains about 30 bacteria. Therefore, a Paramecium can swallow about 43,200 bacteria every day. It has a certain purification effect on sewage. .
Edit species in this paragraph
Classification of Paramecium: Paramecium belongs to the class Ciliates, order Hymenostoma, family Paramecidae. There are 22 species of Paramecium that have been reported in the world. Structure of Paramecium
There are at least the following species common in my country. 1． Paramecium grandis, also called Paramecia caudalis, is 180-280 microns long, with a cone-shaped rear end and an angle of about 45 to 60 degrees at the top of the cone. Both telescopic bubbles have collection tubes. There is a small nucleus, dense and oval. Lives in stagnant water or slow flow with lots of organic matter. 2． Paramecium binucleus is 80-170 microns long and looks like a paramecium, but the rear part is wider than the front part, the rear end is tapered, and the apex angle is nearly 90 degrees. There are two telescopic bubbles and the collection tube is shorter. There are two small nuclei, very small, bubble type. The living environment is the same as that of Paramecia caudalis. 3． Paramecium polymicronucleus is 180-310 microns long and resembles a tail Paramecium, sometimes with three telescopic vesicles. Small nuclear vesicle type, with 3-12 vesicles. The living environment is the same as that of Paramecia caudalis. 4. Green Paramecium has a body length of 80-150 microns. There are green algae growing in the cytoplasm, and the whole body turns green after being cultured in a light place. One small nucleus, dense type. Lives in clear water ponds. 5. Toxic paramecium (killerparamecia) Some strains of paramecium can produce a toxin (paramecium), which can kill other strains of paramecia but is harmless to itself. Therefore, the strains that can produce toxins are called toxic paramecium; the strains that can be killed are called sensitive paramecium, which cannot produce paramecium. The ability of paramecium toxin to produce toxins is determined by two factors. First, its cytoplasm contains a special particle called Kappaparti-cle. The diameter of Kappaparti-cle is about 0.2 microns and the length is about 1 to 5 microns, containing DNA, RNA, proteins, sugars, etc., and is now recognized as an endogenous organism. It can self-replicate and mutate, and the number of kappa granules in each cell can range from a few to hundreds. Paramecium is produced under the control of kappa granules. Another factor is that its cell nucleus contains the dominant gene K. When the nuclear gene K and kappa granules are present in a cell, the paramecium can produce toxins. It can be seen that the toxin is released by kappa granules and the dominant gene K. *** decided together. Kappa granules must be replicated under the influence of the K gene. Paramecium with only nuclear gene K but no kappa granules cannot produce toxins because the nuclear gene K cannot re-produce kappa granules in the absence of kappa granules.
Although the paramecium with only kappa grains and no nuclear gene K could release poison at first, due to the continuous division of cells and the kappa grains could not replicate, the number of kappa grains became less and less, and finally (about 5 to 8 generations) it became Sensitive type without carbachol. The genotypes of radioactive and sensitive Paramecium are as follows: Radioactive-sensitive type K/K + carbograin K/K K/k + carbograin K/k k/k + carbograin k/k
Edit this paragraph Breeding and Purification
Cultivation
Paramecium is an essential feed for the growth of fish seedlings. However, it is difficult to find and catch, so to make up for its shortcomings, it should be raised artificially. The method is: cut the dry rice straw into small sections, soak it directly in water or boil it and then soak it, and use the rice straw leaching solution as the culture medium. Then put the soaked straw and water into a glass container, with water accounting for more than 2/3, and place it in a place with sufficient light. Then go to a humus-rich place to collect seed sources. The water quality there should be clearer than the water quality in the pits and ponds where red worms are fished. Scoop back a bucket of water, put part of the water into a colorless and transparent vial, carefully observe the sunlight, and you will see small white dots suspended in the water. If you can't see any white spots, stir the water in the bucket vigorously, then take the water from the center and put it into a small bottle. Look at the light to see if there are any white spots. If you see small white spots floating in the water, you can pour the water into the culture medium. Control the temperature between 22°C and 28°C, and paramecium larvae will be found after 1 week. Feed it cooked beef juice and split after about 0.5 hours. The process of food digestion by Paramecium