The respiratory and circulatory system
<span>To avoid body damage to the digestive system, the liver produces bile which is being stored in the gallbladder and then releases into the small intestines.
Bile will neutralize the acidic contents which are coming from the stomach by creating an alkaline environment where the intestinal enzymes need to work. The hydrochloric acid which is produced in the stomach increases the acidity of stomach PH for stomach enzymes to digest food. The digestive enzymes which are formed in the small intestine are then damaged by strongly acidic conditions.</span>
Answer:
C. a mutation in the genetic code.
Explanation:
A mutation refers to any change or alteration to the nucleotide sequence of a gene caused by mutagen or mistakes during replication. Depending on the manner of occurrence, mutation can be of different types. In this question, partial DNA sequence for normal hemoglobin is given as: G-G-A-C-T-T-C-T-T while the partial DNA sequence for sickle cell anaemia is given as: G-G-A-C-A-T-C-T-T.
From careful observation of the two two DNA sequences above, it can be realized that a SUBSTITUTION MUTATION from T to A has occurred in the sequence of sickle cell. Note that substitution mutation is the replacement of one base by another in a sequence.
It would be one big letter and one small letter, e.g Dd