The statement "<span>A strand of DNA serves as a model of the synthesis of RNA molecules" is totally a false statement. Each and every DNA strand only serves as a template or a model for the formation of other DNA molecule which was called as the process of replication.</span>
<span>The question says,' the purpose of the mucus found within the respiratory system is to .............. The correct option is B. The mucus found in the respiratory system function by trapping foreign particles that enter into the lungs especially thorugh the nose during breathing, thus mucus aid in protecting the lungs.</span>
<span>The key points about cell theory are as follows:
1. All living organisms are made up of cells; the organisms may be unicellular or multi cellular.
2. The cell is the basic unit of life.
3. New cells are derived from pre-existing cells.
4. All cells maintain homeostasis.
Some new facts have been added to these basic facts; the new facts added include the following:
(A). Energy flow occur withing all living cells.
(B). Hereditary information derived from DNA is passed from cell to cell.
(C). All living cells are made up of the same basic chemical compositions.</span>
I believe that 2 is correct. :)
Answer:
The correct answer is - option C.
Explanation:
CFTR is a short form of cystic fibrosis transmembrane conductance regulator protein which is caused by a recessive mutation in this protein. This mutation results in the accumulation of mucus in secretory organs.
As the disease is a recessive disease, for the mutant phenotype to expressed both copies of the allele required to be recessive.
The mother is negative for the CFTR. Hence, she will not transfer the mutant allele to her child So, the child would have a wild-type phenotype even if the father having two copies of recessive allele.
Thus, the correct answer is - option C.