<span>Pepsin is an enzyme that breaks down proteins into amino acids in the stomach (where the pH is 1-3). Pepsin needs to be in an acidic environment to be activated. The optimum temperature is between 30 oC and 40 oC because the average human body temperature is 37 oC. The optimum pH is the acidic one because your stomach has an acidic pH.</span>
Answer:
B . The hinge joint of the elbow.
Explanation:
Uniaxial joint allows for motion in a single phase.
Answer:
A. True
Explanation:
Hemoglobin is a protein and has two distinct types of polypeptide chains. These are called the alpha and beta subunits. The gene that code for the beta chain undergoes a mutation in a single base that causes sickle cell anemia. Here, adenine base in the genetic code for glutamic acid is substituted with a thymine base.
The genetic code for glutamic acid in the beta chain gene is GAG. The "A" is replaced with "T" and the new code "GTG" codes for valine. Therefore, the mutated hemoglobin has valine in place of glutamic acid. This makes these mutated protein molecules to form aggregates resulting in a change in the shape of RBCs carrying them.
