Answer:
and the other questions you have the arm to 
 
        
             
        
        
        
Answer:
The correct answer is B respiratory system
Explanation:
Respiratory system of our body play a significant role in the inhalation of oxygen into  and exhalation of the waste product known as carbon dioxide from our body.
         Respiratory system basically composed of diaphragm and respiratory muscles.The volume of diaphragm increases during inhalation and decreases during exhalation. This is called the elastic nature of lungs which helps in efficient gas exchange.
 
        
             
        
        
        
Answer:
Oxygen liberated during photosynthesis comes from the splitting or hydrolysis of water in the green plants. Cornelius van Niel experimentally proved for the first time that the oxygen liberated during photosynthesis comes from water and not from carbon dioxide.
 
        
                    
             
        
        
        
Answer:
Since the origin of humans on this planet, they have been trying their best to make their lives easier on this planet. In doing so, human activities have some how heavily damaged the Earth. Many day to day activities of humans are dangerous for the Earth.
Some of the consequences of human activities on the Earth's fresh water are :
Extinction of many aquatic species:
The water consumed by humans comes from the fresh water oceans. As the population of humans is increasing enormously, the water from the oceans is being consumed at dangerous levels. This has caused many species of aquatic animals to become extinct or to be at a verge of extinction as they do  not have a habitat to survive or reproduce.
Pollution:
Many heavy industries, house sewage, farmers dispose waste into the fresh water. Hence, killing aquatic animals and polluting the fresh water ecosystems.
 
        
                    
             
        
        
        
<span>The lymphatic system is considered as the subsystem of the circulatory
system that is composed of networks of vessels, tissues and organs in vertebrates.
Its anatomy is composed of lymph nodes and lymphatic vessels which connect the
other parts systematically. A picture of the lymphatic system is attached below.</span>