Name the chemical reaction that takes place when two amino acids combine to make a dipeptide.
Fig. 3.1 shows the two amino acids glycine and valine. Use the blank space below to draw what occurs when these two molecules join to make a dipeptide.
Angiotensinogen is an inactive protein molecule. When blood pressure falls, angiotensinogen is cleaved to produce a short polypeptide, angiotensin, which stimulates an increase in blood pressure. Fig. 3.2 shows the base sequence in the gene for angiotensinogen that codes for this short polypeptide, the RNA codons and the primary structure of angiotensin.
Complete Fig. 3.2 by adding the missing DNA triplet and the RNA codons.
State the full name of the type of RNA shown in Fig. 3.2.
Use the information in Table 3.1 to explain why the blood pressure in the pulmonary artery matches the pressure in the right ventricle during systole, but is greater during diastole.
People with long-term chronic obstructive pulmonary disease (COPD) usually have blood that is poorly oxygenated as it passes through the lungs. This causes constriction of blood vessels in the lungs. Suggest the likely effect of this on the heart.
Describe the signs and symptoms of COPD that help doctors make an early diagnosis of this condition.