Transport in Mammals
493 questions· page 1 of 50
The graph shows the dissociation curves for haemoglobin at two different partial pressures of carbon dioxide.
Which labelled point on the oxygen dissociation curves will result in the highest concentration of haemoglobinic acid?
Options
A A
B B
C C
D D
Which statements about the transport of carbon dioxide in the blood are correct?
1 Carbonic anhydrase catalyses the reaction of carbon dioxide and water to form carbonic acid.
2 Carbonic acid dissociates into hydrogen ions and hydrogencarbonate ions.
3 Some carbon dioxide combines with haemoglobin to form carbaminohaemoglobin.
4 Haemoglobin readily combines with hydrogencarbonate ions to form haemoglobinic acid.
Options
A 1, 2 and 3
B 1 and 2 and 4
C 1, 3 and 4
D 2, 3 and 4
What happens as a result of the blood pressure in the left ventricle becoming higher than the blood pressure in the left atrium?
Options
A The left atrioventricular valve closes.
B The left atrioventricular valve opens.
C The semilunar valve in the aorta closes.
D The semilunar valve in the aorta opens.
The diagram shows the structure of an amphibian heart and the movement of blood through it.
Which statements about differences between the amphibian heart and a human heart are correct?
1 The hearts have a different number of ventricles.
2 The hearts have a different number of atrioventricular valves.
3 A septum is absent in the amphibian heart and a septum is present in the human heart.
Options
A 1, 2 and 3
B 1 and 2 only
C 1 and 3 only
D 2 and 3 only
A mutation in one of the genes that codes for haemoglobin changes the affinity of haemoglobin for oxygen.
This mutation lowers the partial pressure of oxygen at which haemoglobin is 50% saturated with oxygen.
Which row shows the effect of the mutation on the affinity of haemoglobin for oxygen and the change in the position of the oxygen dissociation curve for haemoglobin?
Options
| the effect of the mutation on the affinity of haemoglobin for oxygen | change in the position of the oxygen dissociation curve for haemoglobin | |
|---|---|---|
| A | higher | shift to the left |
| B | higher | shift to the right |
| C | lower | shift to the left |
| D | lower | shift to the right |
Which processes are responsible for the Bohr shift?
1 Carbon dioxide reacts with haemoglobin to form carbaminohaemoglobin.
2 Carbon dioxide reacts with water to form carbonic acid.
3 Haemoglobinic acid is formed from the dissociation of carbonic acid.
Options
A 1, 2 and 3
B 1 only
C 2 and 3 only
D 3 only
A student viewed a drop of human blood with a microscope and described a cell as having a very large diameter and a U-shaped nucleus that occupies half the volume of the cell.
Which type of cell was the student viewing?
Options
A monocyte
B neutrophil
C red blood cell
D lymphocyte
The diagrams show three types of blood cells, which are all drawn to the same scale.
Which row shows the characteristics of the cells?
Options
| name of blood cell X | engulfs pathogens by endocytosis | each responds to one antigen | |
|---|---|---|---|
| A | monocyte | Y | Z |
| B | monocyte | Z | Y |
| C | lymphocyte | Y | Z |
| D | lymphocyte | Z | Y |
The graph shows oxygen dissociation curves for three animals. The shape of each curve is influenced by respiration rate and the affinity of haemoglobin for oxygen.
What can be concluded from the graph?
Options
A Animal 1 has haemoglobin adapted to have a higher affinity for oxygen than animal 2.
B Animal 3 has haemoglobin adapted to have a higher affinity for oxygen than animal 2.
C Animal 3 has haemoglobin adapted to maintain a lower respiration rate than animal 2.
D Animal 1 has haemoglobin adapted to maintain a higher respiration rate than animal 2.
Which statements about a mammalian heart are correct?
1 The right atrium and right ventricle contain deoxygenated blood going to the lungs.
2 The left atrium and left ventricle contain oxygenated blood going to the pulmonary circulation.
3 The left ventricle has a thicker wall than the right ventricle and delivers blood at higher pressure.
4 The pressure of blood in the aorta is less than that in the pulmonary artery.
Options
A 1, 3 and 4
B 1 and 3 only
C 2, 3 and 4
D 2 and 4 only