Answer: Four pulmonary veins.
Explanation: Oxygen and nutrient rich blood will flow from the lungs back into this part called the left atrium (Or as some will call it, the left upper chamber in the heart). From there, it goes through four pulmonary veins.
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This injury is fatal because, The phrenic nerve regulates breathing and operates the diaphragm.
<u>Explanation:</u>
The motor ability is provided by the Nerve called Phrenic nerve to the diaphragm. This is a muscle that is very important for the respiration to take place in human. When a damage or injury occurs to the Phrenic nerve, it may result in the paralysis of diaphragm. 
When this is damages there may be difficulties in breathing and only small amount of air can be inhaled. Thus the paralysis of this nerve results in the prevention of the victim to find difficulties in respiration. Thus, the example given is fatal because, the phrenic nerve regulates breathing and operates the diaphragm.
 
        
             
        
        
        
 The answer is Euglena. Euglena is a genus of single-celled flagellate eukaryotes. It is a large genus of unicellular protists, which have both plant and animal characteristics. All are motile by means of a flagellum. Most have chloroplasts (alga and plant characteristic). Euglenids are believed to descend from an ancestor that took up green algae by secondary endosymbiosis.
        
                    
             
        
        
        
The biome that usually have this type of vegetation are tundras or polar grasslands.
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Metaphase. In all versions of metaphase the chromosomes line up in the middle of the cell.