The answer is B: Water breaks down into oxygen molecules for respiration.
 
        
                    
             
        
        
        
Answer:
Rock 
Explanation:
Minerals are inorganic substances that occur naturally in nature and have a  
a definite chemical composition and a crystalline structure while rocks may consists of one or many minerals together along with some organic remains due to which it may not look shiny and crystalline from outside.  
Here, the two characteristics that enable the reader to identify the object given by grandmother to Emily as rock  are –  
a)	Looks ugly on the outside (shows the presence of organic matter)
b)	solid purple color with pretty crystals (crystalline structure inside)
 
        
             
        
        
        
Answer:
an S strain and mix it with cells of an R strain
 
        
             
        
        
        
The right option is; B) the total variety of organisms on Earth 
The total variety of organisms on Earth explains biodiversity
Biodiversity is the variety and variability of all species (different plants, animals and microorganisms) from all sources (marine, terrestrial and other aquatic ecosystem) on earth or within a particular region. Biodiversity involves genetic diversity, species diversity and ecosystem diversity which all functions together to form the complexity of life on earth.
 
        
                    
             
        
        
        
Below are the options:
Having two phases of meiosis allow for more unique cells to be produced.
Meiosis is a form of asexual reproduction which leads to more genetic variation.
Meiosis produces 4 haploid daughter cells which all contain identical DNA segments.
<span>Crossing over during metaphase allows segments of DNA from 2 parents to SWAP and produce non-identical haploid cells.
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The answer <span>Meiosis is a form of asexual reproduction which leads to more genetic variation</span>