A. Group of cells
Cells - Tissue - Organ ...
If you want to know more - look for "Biological Organisation"
        
                    
             
        
        
        
The circulatory system and respiratory system are protected by your skin, muscles, and ribs.
        
                    
             
        
        
        
Answer:B
Explanation:
Because aerobic respiration produce alot of energy (looking at kreb's cycle, ETP,) 
 
        
             
        
        
        
Mitosis form of cell division marks in an enlarged germ cell pool, Mitosis is a procedure where a single cell splits into two identical daughter cells (cell division).
<h3>What is mitosis and meiosis?</h3>
There are two kinds of cell division: mitosis and meiosis. Most of the time when people refer to “cell division,” they mean mitosis, the procedure of making new body cells. 
Meiosis is the kind of cell division that creates egg and sperm cells. Mitosis is a actual procedure for life.
Thus, Mitosis form of cell division marks in an enlarged germ cell pool, Mitosis is a procedure where a single cell divides into two same daughter cells.
To learn more about Mitosis  click here:
brainly.com/question/26678449
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Answer:
mosses
Explanation:
Simple species that can tolerate the often- harsh environment become established first. These organisms help enrich the soil, allowing other species to become established. The first organisms to appear in areas of primary succession are often mosses or lichens.