Answer:
The circulatory and respiratory systems absorb oxygen from the air and transfer it to all parts of the body while absorbing carbon dioxide from the body and releasing it into the air. When a person inhales, the lungs expand and fill with fresh air.
Explanation:
 
        
             
        
        
        
Answer and Explanation:
cross: BbTt x bbTt
<u>Cross for B gene</u>
Parental ) Bb   x   bb
Gametes) B   b   b   b
Punnet square)  B     b
                   b     Bb    bb
                   b     Bb    bb
F1) Genotypic proportion: 2/4=1/2 Bb : 2/4=1/2 bb
      Genotypic ratio 1:1
      Phenotypic proportion: 2/4=1/2 B- : 2/4=1/2 bb
      Phenotypic ratio   1:1
<u>Cross for T gene</u>
Parental ) Tt   x   Tt
Gametes) T  t     T   t
Punnet square) T       t
                   T     TT    Tt
                   t      Tt    tt
F1) Genotypic proportion 1/4 TT
                                           2/4 Tt
                                           1/4 tt
      Genotypic ratio  1 : 2 : 1
       Phenotypic proportion: 3/4 T-
                                               1/4 tt
      Phenotypic ratio 3 : 1
 
        
             
        
        
        
Answer:
The culture might not be stained properly or the culture might be too old.
Explanation:
Gram staining is done to differentiate between gram-positive and gram-negative bacteria according to the difference in their cell wall. In gram staining, the gram-positive bacteria appears violet and gram-negative bacteria appear pink in color.
Therefore if a pure culture contains have both red and purple cocci that it can be concluded that the gram stating was not done properly like too much destaining was done or too much safranin was used or maybe the culture is too old so that cell wall of some bacteria degrades. 
 
        
             
        
        
        
Answer:
 Sickle cell anemia is one of a group of disorders known as sickle cell disease. 
Explanation: