C- Single-celled organisms and soft, boneless animals.
        
                    
             
        
        
        
The structure is a phospholipid bilayer. There are many phospholipids which contain a water loving phosphate end and a water hating lipid (fatty) end. The phosphate ends all point out words while the fatty ends are inside.
The purpose is protection of the cell as well as allowing certain molecules to enter and exit the cell
        
                    
             
        
        
        
This response helps decrease body temperature. Another example of negative feedback has to do with blood glucose levels. ... If a raise in body temperature (stimulus) is detected (receptor), a signal will cause the brain to maintain homeostasis (response).
        
             
        
        
        
Hello!
If you look at a zipper, you'll see that it doesn't have a wheel or an axle. A zipper links the <span>protruding teeth that the zip contains. Your answer would be B!
You can feel free to let me know if you have any questions regarding this!
Thanks!
- TetraFish</span>
        
                    
             
        
        
        
The left side of the heart collects oxygen-rich blood from the lungs and pumps it to the body. The left and right sides of the heart are divided by walls<span> called septums. There is an atrial septum that separates the right and left atriums, and a ventricular septum that separates the right and left ventricles.</span>