Distribution of bryophytes is global. They are found everywhere except the sea. They usually grow in moist shady environments. Also grows in polar and desert regions. 248 species of 74 genera of 34 tribes have been identified in Bangladesh. Today, 15,600 (according to many, 24,000) species of 960 genera of bryophytes are distributed worldwide.

The word Bryophyta is formed from the Greek words bryon meaning moss and phyton meaning plant. Bryophyta means mossy plants. Bryophytes are green avascular plants composed of parenchyma cells, divided into thalloids or stems and leaves. The division of bryophytes is called Bryophyta. In 1864 scientist Braun first used the term Bryophyta. Plants of the class Bryophyta are called amphibious plants as water is essential for fertilization and life cycle. The smallest bryophyte is Zoopsis argentea. Zoopsis is 5 mm in length. And the largest bryophyte is Dawsonia. The length of Dawsonia is 50-70 cm (Dawsonia superba, Dawsonia longifolia Dawsonia longiseta).

All the plants of the world are divided into two groups based on having flowers. Phanerogams are plants and cryptogams are plants. The non-flowering or cryptogamous are divided into three categories. Thallophyta, Bryophyta and Pteridophyta. Thallophyta are immature cryptogams. Bryophyta and Pteridophyta are hybrid cryptogams. Bryophyta are connecting plants between Thallophyta and Pteridophyta.

Dyspnea is the discomfort or pain that occurs when the breathing rate increases due to any reason. Lack of oxygen, asthma, anemia, epilepsy etc. can cause dyspnea.

A temporary pause in breathing due to any reason is called apnea. Causes of apnea are poisoning, sudden increase in blood pressure, unconscious swallowing of food, immersion in water, electric shock etc.

If the oxygen supply to the cells is low due to any reason, it is called hypoxia. Hypoxia can be caused by asthma, pneumonia, anemia, poisoning, excessive bleeding, mountain climbing etc.

When the oxygen supply to the cells is completely stopped due to some reason, it is called anoxia. It causes body weakness, headaches and dizziness, personality changes and memory loss.

1. First, the injured person should lie flat on his back. Neck, neck and chest clothes should be loosened.
2. If there is any foreign object inside the patient’s mouth, it should be removed with fingers. If there is water or mucus inside the mouth, it should be thrown out by tilting the head.
3. One hand should be placed under the patient’s neck and the other hand should be held above the snout. If the tongue gets stuck in the throat, it will run out and open the airway.
4. The rescuer should place one hand on the patient’s forehead and with the thumb and forefinger of that hand, pinch both nostrils of the patient in such a way that there is no gap and air cannot escape.
5. After putting a mask on the face, try to force air into the patient’s mouth so that the air reaches the lungs. Air pressure should be gentle for small or children.
6. Blow 20 times per minute and continue this process until the patient’s heart starts beating.
7. The patient’s chest should be massaged. During the massage, the chest may need to be pressed down about one and a half inches. For younger babies, massage with three fingers just below the nipple.
8. The patient’s chest should be taken care of, if the chest starts to rise and fall, air should be stopped by the mouth. The patient should be kept in this position for one to one and a half hours. After understanding the situation, take it to the doctor.

1. Artificial respiration is essential to save life in emergencies such as drowning, neck and head injuries, electrocution, carbon monoxide poisoning, fatal injuries, etc.
2. When the diaphragm and optional muscles are exhausted due to the use of analgesics and weakness of the patient.
3. Even if the heart is strong, breathing stops.
4. Breathing rate is greatly reduced due to lack of oxygen.
5. When brain cells rapidly deplete, artificial respiration is needed to keep them alive.
6. To maintain the vitality of the lungs and heart.
7. During earthquakes and floods.
8. Heart attack or cardiac arrest.
9. Artificial respiration becomes necessary if breathing is abnormal or obstructed after delivery.
10. Gaseous exchange between blood in the lungs and capillary network maintains vitality in the respiratory center and heart. In this the lungs can function normally.

Artificial respiration can be divided into two main categories. Manual method and mechanical method.
1. Manual Methods
(i) Attempting to force air into the patient’s lungs by blowing forcefully with a mouthpiece.
(ii) Air is forced into the patient’s lungs by applying a mouthpiece to the nose.
(iii) Applying air to the mouth and nose of children.

2. Instrumental Methods
(i) If it is not possible to apply a mask over the patient’s face, force air into the lungs by blowing forcefully through the mouth.
(ii) Placing a balloon-like bag over the patient’s mouth and pumping air into the patient’s lungs by rhythmically pressing the bag.
(iii) Artificial respiration can be given using automatic electrical devices or ventilators.