Yes Carbon dioxide is necessary for photosynthesis because Photosynthesis didn't go on because there was no Carbon dioxide in flask X.
The carbon dioxide was absorbed by the sodium hydroxide. In flask Y, the colour of the iodine solution turned blue black. This is because starch was present in the leaf of flask Y. Starch was present because it underwent photosynthesis.
 
        
             
        
        
        
Answer:
84
Explanation:
42 X 2 since it is a pair
 
        
                    
             
        
        
        
The independent variable is the one variable you manipulate in the experiment
The dependent variable (or responding variable) changes as a result of the independent variable  
        
                    
             
        
        
        
Radiation can damage DNA. This could result in a change in the proteins which make up the plant's physical structure. 
<span>For example, a plant might have a gene for purple pigment which makes its flowers purple. Radiation might change the DNA sequence so that the directions for making the purple pigment tell it to stop prematurely, and the result might be white flowers rather than purple flowers.</span>
        
             
        
        
        
“Grass is a monocotyledon plant, herbaceous plants with narrow leaves growing from the base. A common kind of grass is used to cover the ground in a lawn and other places. Grass normally gets water from the roots, which are located in the ground.” This is NOT my information I found it on Wikipedia hope this helps