I believe the biosphere is fragile, because over time all of the pollution us humans have made; If its from air pulloution, acid rain or even water pollution. the toxic acids over time have made the biosphere and the ozon layer weaker and more thin. which causes the biosphere to become weaker.
        
                    
             
        
        
        
The nucleus contains the cells DNA(genetic material) which is basically the recipe for making proteins. mRNA is first transcribed off of DNA and then in translated(by ribosomes) to polypeptides(proteins). 
 
        
             
        
        
        
I am not entirely sure about this. So maybe my response can help you find the answer a little better if my answer is not entirely right? 
These last three questions are referring to everything you just worked on. So all you would have to do is refer back to your previous answers. Recall that the titles of the "part 1, 2, and 3" are titled "crossing beak color and tail-feather length", "crossing beak color and feather color", and "mapping tail-feather length and feather color". 
1.List the distances between each pair of genes: 
beak color and tail-feather length: 20 MU 
beak color and feather color: 16 MU 
tail-feather length and feather color: 4 MU 
2.Which two alleles are the farthest apart? 
(the one that is 20 MU apart) Y and L 
3.Which two alleles are the closest together? 
(the ones that are 4 MU apart) L and B 
        
             
        
        
        
Answer:
Nose, Trachea, Bronchi, Lungs (for inhalation)
Explanation:
Just reverse the answer for order of exhalation
 
        
             
        
        
        
Genes in DNA or responsible for the traits an organism has. This is caused by Dominant and Recessive Traits. Remember that Genotypes are the genetic letters such as RR, Rr, and rr. Phenotype is physical traits.
Dominant Traits are more likely or always show in the offspring. The Dominant Genotype uses Capital letters such as RR. 
Recessive Traits are less likely to show up. Their Genotype use lower case such as rr. Now genotypes of Rr have one dominant trait and one recessive trait. If the dominant trait was black fur and the recessive white fur, the offspring will be black fur because dominant traits overpower the other.
To understand how to know if an organism will have Dominant or Recessive Genes, you have to use something called a Punnet Square. Lets imagine 2 parents both have the genotype Rr. R is Black fur and r is white fur. As you can see from the chart, 3 of 4 boxes have Rr and 1 rr. Since there is a Dominant Trait with a Recessive, they will show a Dominant Phenotype, or Black fur. This has 3/4 chance and a 1/4 chance for white fur in the offspring.
 | R. r
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 R | Rr. Rr 
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 r | Rr. rr