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<u>cardic muscles:</u> are present only in the heart .single cell is not very strong by itself, millions of cardiac muscle cells working together are easily able to pump all of the blood in the body through the heart in less than a minute. Cardiac muscle cells have a branched shape so that each cell is in contact with three of four other cardiac muscle cells.
<u>characteristics  of cardic muscles: </u> one nucleus ,striated, involuntary, branched and joined to one another by intercalated discs that contain  gap junctions for depolarization between cells and  hold the fibers together when the heart contracts.
 
        
        
        
1 you run out of fuel 2 it takes a long time 3 it’s hard to get back 4 the conditions are constantly changing making it harder to predict what could happen. Look at Apollo 12 as a example
        
             
        
        
        
Answer:
Parasitism describes a relationship between two organisms where one gets benefit and other get harm. 
Explanation: 
Parasitism is a type of symbiotic association that is present between two different organisms. In association, one organism gets benefit from the other and the other is damaged. For example, association between mosquitoes and human is parasitism because mosquitoes get benefit in the form of food while human is damaged due to disease cause by mosquito biting. 
 
        
                    
             
        
        
        
Thus, light energy is initially converted to chemical energy in the form of two compounds: NADPH, a source of energized electrons ( "reducing power"); and ATP, the versatile energy currency o that the light reactions produce no sugar; that happens in the second stage of photosynthesis, the Calvin cycle.
        
             
        
        
        
Restriction enzymes are DNA cutting enzymes found within bacteria. They can cut the DNA molecule.