The Dhaka Times Desk We know that the process of reproduction of any animal on earth is the union of male and female. However, some animals can reproduce without sex. This is possible only through the process of parthenogenesis. This information is known through researchers.
Basically parthenogenesis is a natural form of asexual reproduction; So that the growth and development of the fetus takes place without fertilization. In animals, parthenogenesis means the development of an embryo from an unfertilized embryo.
The word parthenogenesis is derived from the combination of the Greek words 'parthenos' and 'genesis'. Parthenos means 'virgin' and genesis means 'creation'.
Parthenogenesis occurs naturally in some plants and insects. Also some amphibians, reptiles, birds and fish. However, in other species it is rare and usually seen in captivity.
Damian Chapman directs the shark and ray conservation program at the Mote Marine Laboratory and Aquarium in Sarasota, Florida. This tends to happen in situations where women are separated from men, he told the media.
Meanwhile, last week in The City of Portsmouth College in Portsmouth, United Kingdom, a snake of the rare Brazilian rainbow boa species gave birth to 14 babies without coming into contact with male snakes! The college authorities said that the snake has not come in contact with any male snake in the last 9 years.
On the other hand, in an aquarium in the state of North Carolina in the United States, a stingray fish named Charlotte is pregnant in the process of parthenogenesis. However, it died last week before the baby was born. Although she never gave birth and it is not clear whether she was ever pregnant.
One form of parthenogenesis is when a woman's egg actually fuses with another cell, according to media reports. Cells left over from a process that allows a woman to produce an egg. This cell is also known as a polar body. What gives the egg its genetic information is usually found in the sperm. The cell begins to divide and this leads to the formation of an embryo.
Damien Chapman told the media that an animal's egg naturally needs sperm to create an embryo. However, the process of parthenogenesis does not require sperm. He also suggests that offspring from parthenogenesis also have less genetic diversity, which may lead to developmental problems.
However, it is not clear how common parthenogenesis is in the wild. But it has also occurred outside of captivity in the small-toothed sawfish, an endangered species in Florida's coastal waters, he said. Source: ABCNews.
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How to prevent dengue
Dengue is a mosquito-borne viral fever. This fever is different from other viral or bacterial fevers. However, this fever is not contagious in any way. This viral fever can occur alone or in combination with other viruses (chikungunya, yellow fever, Burma forest, flu, respiratory syncytial) and bacteria (pneumococcus).
Dengue fever is divided into two categories depending on the severity of symptoms and fever.
1. Common dengue fever
2. Dengue fever with bleeding.
In the case of common dengue fever, the following symptoms are mainly seen-
1. Sudden high fever lasting 2 to 7 days.
2. Severe headache.
3. Pain behind the eyes.
4. Along with the fever, red rash appears all over the body.
5. Severe pain in whole body as well as back pain.
6. Nausea or vomiting.
7. A rash or red bumps on the skin.
In case of dengue fever with bleeding:
1. Bleeding from nose, mouth or vomiting with high fever within 2 to 48 hours.
2. Fluid accumulation in chest or abdomen along with fever.
If any of these symptoms appear, seek medical attention immediately.
On the other hand
Wait at home for the first 3 days of fever. On the other hand, sponge the whole body with water every now and then. This will reduce the level of fever. Drink enough water and rest. After that, if the fever does not decrease or if it continues to increase after some time, consult a doctor immediately.
Things to do to prevent Dengue:
1. Try to keep the surroundings of the house as clean as possible.
2. If there are flower tubs or broken plastic bottles, can shells, tires or polythene inside the house, clean them quickly and drain the accumulated water from the flower tubs.
3. Spray or fog at least 3 times a week to kill mosquitoes.
4. You can keep mosquito repellent cream with you while going out.
5. After evening, younger and older members of the household should use mosquito nets.
6. Clean up any accumulated rain water, as this is the time when Aedes mosquitoes lay their eggs.
7. On the other hand, you can use mats along with mosquito nets to avoid mosquito infestation.
8. Since Aedes mosquitoes bite during the day, it is important to avoid sleeping with mosquito nets while sleeping during the day. Source: https://dmpnews.org
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