Answer:
Gradually, as generations of elephants continued to selectively use and develop their trunks.
Explanation:
Jean-Baptiste Lamarck was  famous French Naturalist. He was a soldier, a biologist and an academic. He gave an early theory of evolution known as the theory of Lamarckism. 
It was Lamarck who first believed that elephants earlier had small trunks. But eventual when there was scarcity of food and water, the elephants stretched out its trunk to reached out for food such as trees and also water. And as a result their offspring inherited long and powerful trunk. 
In his theory of Lamarckism, he believed that the species passes on its traits to the offspring which they acquired through their use in their lifetime. In this case, the elephants might have used their trunks in such a way that they became long and strong over time and they passed tis trait to their babies. 
 
        
             
        
        
        
Answer:
the answer is biochemistry
 
        
                    
             
        
        
        
False teeth help the digestive system by chewing pieces of food into smaller pieces but it is not part of it. 
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<span><span>The blood cells containing hemoglobin,  that transports oxygen (O2) to the body tissues of vertebrates, are called red blood cells.</span> Red blood cells (RBCs), are also referred to as red cells, red blood corpuscles, haematids, erythroid cells or erythrocytes<span>, (from Greek erythros for "red" and kytos for "hollow vessel"..RBCs take up oxygen in the lungs and release it into tissues while squeezing through the body's capillaries.</span></span>
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The endoplasmic reticulum, or ER, and Golgi apparatus, prepare molecules, including proteins, hormones and lipids, and package them in vesicles for transport. Rough ER is studded with ribosomes that synthesize proteins, while the smooth ER manufactures lipids.