Answer:
The main purpose of the circulatory system is to transport blood, oxygen, nutrients and hormones to and from different cells and tissues throughout the body.
Explanation:
This system works hand-in-hand with the respiratory system to facilitate the exchange of oxygen and carbon dioxide within the blood per the alveoli in the lungs.
 
        
             
        
        
        
<span>Everyone has cells because these are the building
blocks of life. These tiny particles that clump into groups that form tissues,
organs, and organ systems are
what makes organisms distinct from non-living things that exist on Earth. Where
there are cells, life is present, and in its absence life cannot exist as we
know of today. Cells are responsible for bringing different species of
organisms that are found in different ecosystems all over Earth. They are tiny
but in groups they are responsible for every living organisms that have existed
through time.  </span>
        
             
        
        
        
Answer:
d) harvesting and threshing both.
Explanation:
Hope it helps you...
 
        
             
        
        
        
Answer:
they have diffrent part are shape
 
        
                    
             
        
        
        
Answer:
This element is carbon.
Explanation:
You might be quick to think the answer is something like hydrogen and oxygen because both form to make water. But understand that the question is not asking about important elements in life, just which element makes up organic molecules. This element happens to be carbon. 
It's important to understand that carbon is lucky in that it has 4 valence electrons and is able to bond with other important elements, like F, N, and especially H. The bond between C-H is essential in organic chemistry because it represents the structure of an organic molecule and helps with the IUPAC naming of organic molecules. It also suffices to say that there is a cycle for carbon in the carbon cycle, which transports carbon from one place in our world to the other. 
So, it suffices to say that carbon is in fact essential for making up organic molecules.