Answer:
D. All cells must be reproduced by another cell.
Explanation:
The cell theory has a couple key components, which are as follows: 
#1. Cells are the basic unit of life.
#2. Cells have hereditary data that is passed down to their offspring.
#3. All cells come from preexisting cells.
#4. All organisms, both unicellular and multicellular, are made of one or more cells.
#5. Energy flows through cells.
#6. All cells have a similar composition.
 
        
                    
             
        
        
        
C. the cell membrane.
the membrane let's things in and out of the cell.
        
                    
             
        
        
        
Answer:
Wet Cell Disadvantages
Wet cell batteries are potentially more dangerous and slower to charge than AGM batteries.
Wet cells emit hydrogen gas during normal operation and especially during charging.
 
        
                    
             
        
        
        
If the partial pressure increases, then the DO concentration in water will also increase. When the altitude is increasing, the total atmospheric pressure decreases, and then the partial pressure of oxygen is also decreasing
        
             
        
        
        
Answer:
The statement that says that In "gastrulation" cells begin to differentiate and they form different types of tissues so that they can accomplish different purposes in the body, is true.
Explanation:
Gastrulation involves a process of cell division, migration and differentiation, being one of the stages of embryonic development.
Cell differentiation and migration in gastrulation leads to the formation of germ layers, which are responsible for forming different tissues and fulfilling different functions in the body:
- <em>The outermost lamina is called the </em><em>ectoderm</em><em>, which can give rise to nerve tissue and part of the skin tissue.
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- <em>The </em><em>mesoderm</em><em> is the middle lamina, and from it vascular, bone, muscle, and joint tissue can develop, as well as tissues of excretory and reproductive organs.  </em>
- <em>Endoderm</em><em> corresponds to the internal lamina, forming in great part the mucous membrane of the organs of the digestive system.
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It is true, then, that <u>In gastrulation cells begin to differentiate and form different types of tissues so they can accomplish different purposes in the body</u>.