You have to put a lid on petri dishes in order to ensure that no outside contaminants get inside the dish.
 
        
             
        
        
        
The germs from her hands mixed with those in the petri dishes and some were contaminated 
        
             
        
        
        
<span>The body is constantly changing, no matter what age. It has to maintain homeostasis, or balance at all times or illness/death occurs. If your body is weakened, it then becomes harder to maintain this state. If one component goes out of balance; ie, water content, it affects the whole body. Swelling(edema) CHF(serious heart problem) kidneys may be overtaxed/unable to release the extra fluid. As the body ages organs naturally become less efficient, therefore making homeostasis more challenging.</span>
        
             
        
        
        
Answer:
Like all other cellular membranes, the plasma membrane consists of both lipids and proteins. The fundamental structure of the membrane is the phospholipid bilayer, which forms a stable barrier between two aqueous compartments.
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