<span>sexual reproduction</span><span>
Sexual reproduction provides genetic variation because the sperm and egg that are produced contain different combinations of genes than the parent organism.  Sexual reproduction involves meiosis which is the process of a cell doubling its DNA, shuffling its genes and then dividing the shuffled DNA among four cells.</span>
        
                    
             
        
        
        
Answer and Explanation:
1. Amino-acid sequence is the primary structure of a protein
2. Alpha helices, beta sheets and coiled coils refers to the protein folding and they represent the secondary structure of a protein
3. Protein ensemble formed by alpha helices, beta sheets and coiled coils represent the tertiary structure of a protein
4. Macromolecules with multiple polypeptides form globular or fibrous protein structures (quaternary structure)
 
        
             
        
        
        
GnRH<span> stimulates (causes) the pituitary gland to produce </span>follicle stimulating hormone<span> (</span>FSH<span>), the hormone responsible for starting follicle (egg) </span>
        
             
        
        
        
Answer:
Harshey and chase labeled T2 bacteriophage with radioactive sulfur and radioactive phosphorus. As DNA contains phosphorus, not protein and protein contain sulfur, not phosphorus, therefore, the presence of radioactivity in cell can determine which is the genetic material
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Then Harshey and Chase infected <em>E.coli</em> with T2 bacteriophage and centrifuged the cell. They found radioactive phosphorus in cell pellet and radioactive sulfur in supernatant.
So by this experiment, they concluded and proved that DNA is the genetic material that gets transfer from one generation to another.
 
        
             
        
        
        
Answer:
Explanation:
Gas exchange occurs at the alveoli in the lungs and takes place by diffusion. The alveoli are surrounded by capillaries so oxygen and carbon dioxide diffuse between the air in the alveoli and the blood in the capillaries.