Answer:
true is the correct answer
 
        
                    
             
        
        
        
Answer:
The correct answer is B make cells produce a functional CFTR protein.
Explanation:
Cystic fibrosis is a disease that is caused due to the mutation in the transmembrane protein known as cystic fibrosis trans membrane conductance regulator or CFTR. Cystic fibrosis trans membrane regulator proteins helps in the formation of thin mucus and due to the mutation in CFTR the mucus becomes thick.The disease cystic fibrosis basically affect the respiratory system.
  If gene therapy is used to treat cystic fibrosis then it can replace the mutated CFTR gene with a functional one so that the cell containing CFTR gene can produce functional CFTR protein.
  
 
        
             
        
        
        
The question is B soil erosion upstream
 
        
                    
             
        
        
        
Answer:
10 chromosomes/sister chromatids
Explanation:
Prophase is the first stage of cell division (mitosis). Prior to the cell entering the actual division stage, it undergoes a phase where it prepares its content and most importantly undergo the duplication of its genetic material (DNA). This DNA are found as chromosomes. It undergoes replication of its DNA in the S-phase of interphase stage.
Since Arabidopsis thaliana has 10 chromosomes, and each chromosome holds one DNA molecule, 10 molecules of DNA will be present in the mustard plant's genome. These 10 molecules of DNA will be replicated on another copy of chromosome which is identical to the template. This chromosomes are called SISTER chromatids i.e. replicated chromosome. Each sister chromatids are held together at the centromere and are considered one individual chromosome until they separate during anaphase stage.
Hence, at the Prophase stage, before separation, each sister chromatid (replicated chromosome) is considered as one chromosome. Thus, in the mustard plant with 10 chromosomes, it will possess 10 sister chromatids or chromosomes at the Prophase stage. 
N.B: When sister chromatids separate during anaphase stage, they will be regarded as individual chromosomes.
 
        
             
        
        
        
Both are 50%, this is because Rr is dominant in a purple stem and rr is recessive in a green stem. By crossing these plants Rxr= Rr and rxr= rr.