Random, generic questions

Question 1

when CO2 enters a red blood cell, what acid is formed and which enzyme is involved in this reaction?

Answer 1

carbonic acid and carbonic anhydrase

Question 2

when oxygen joins with haemoglobin, what compound is formed?

Answer 2

oxyhaemoglobin

Question 3

what are the 2 nodes in the heart that control the electrical activity of the heart?

Answer 3

sino-atrial node, and the atrial-ventricular node