I think it might be the third on I’m not sure completely wait on a second person
        
             
        
        
        
Answer:
Because natural selection selects for it. Thus it persists.
Explanation:
You have to understand heterozygote advantage. Basically, it's where heterozygotes have an advantage over homozygotes. In the case of sickle cell disease, heterozygotes have an advantage, and natural selection favors whatever is advantageous. Thus, because heterozygotes each have one recessive sickle-cell allele, as natural selection favors the heterozygotes, the recessive sickle-cell allele persists and remains in the gene pool.
 
        
             
        
        
        
The correct answer is D.
 The domain is the broadest category in the classification of living organisms. All the living organisms are placed in three domains, which are archaea, bacteria and eukaryotes. The prokaryotes are separated into two groups, that is archaea and bacterial based on the differences in their 16S rRNA genes. Amoeba is classified as an eukaryotes because, its cell is more developed than that of bacteria. 
 
        
                    
             
        
        
        
Explanation:
photosynthesis converts carbon dioxide and water into oxygen and glucose.glucose is used as food by the plant and oxygen as a by-product.
cellular respiration convert oxygen and glucose into water and carbon dioxide water carbon dioxide a byproduct and ATP is energy that is transformed from a process. 
 
        
             
        
        
        
Answer:
A clonagem é a obtenção de duas células idênticas com o mesmo código genético que o produto da reprodução assexuada.
Nos mamíferos, a clonagem ocorre através de células somáticas, onde há um núcleo doador e um oócito que se unem por meio de um choque elétrico, formando o embrião que resultará em um ser vivo clonado, um exemplo de essa era Dolly, a ovelha.
Explanation:
Na clonagem de mamíferos, o embrião é responsável por ter caracteres da ovelha doadora, ou seja, será a imitação do código genético desse animal que empresta a célula doadora ao úbere.