Transport in Animals: Biology 0610 (Cambridge O Level / IGCSE)
Syllabus 9.1, 9.2, 9.3, 9.4 · Strand 9 Transport in animals
- Questions
- 10
- Total marks
- 53
- Tier mix
- 4 Core · 6 Extended
0 of 10 questions completed
Syllabus coverage
- 9.1 2 questions completed
- 9.2 4 questions completed
- 9.3 2 questions completed
- 9.4 3 questions completed
Animals need a transport system to carry substances between cells and the outside world, and this topic (syllabus 9.1 to 9.4) covers the mammalian circulatory system. A circulatory system is a network of blood vessels with a pump, the heart, and valves that keep blood flowing one way. Extended candidates compare the single circulation of a fish with the double circulation of a mammal, in which blood passes through the heart twice per circuit, an arrangement that keeps blood pressure high and delivery efficient.
At the centre is the heart, with muscular walls, four chambers and valves that prevent backflow; its left side has a thicker wall because it pumps blood further, around the whole body. Blood travels away in arteries, returns in veins and exchanges materials in thin-walled capillaries, and each vessel’s structure suits the pressure it handles. Blood itself is made of red blood cells carrying oxygen as oxyhaemoglobin, white blood cells defending against pathogens, platelets involved in clotting, and plasma transporting dissolved substances. Understanding coronary heart disease and the effect of exercise on heart rate rounds out the topic.
The exam-style questions below are original, written to match this objective, each with a full worked solution so you can check your reasoning step by step.
Question 1
A veterinary science student separates a small blood sample from a goat and studies its components under a microscope. She finds that most of the sample's volume is a pale yellow liquid, which is not made of cells. This liquid carries the blood cells themselves, together with dissolved food molecules, urea, hormones and carbon dioxide, around the goat's body.
Which component of blood is being described?
Question 2
A workplace wellness programme offers free heart check-ups to employees aged over 40. During each check-up, a nurse takes several measurements of heart activity and asks each employee about their diet, exercise habits, smoking history and family medical history, before giving health advice.
(a) State two ways, other than measuring blood pressure, in which the activity of a person's heart can be monitored. [2]
(b) Describe coronary heart disease in terms of what happens to the coronary arteries. [2]
(c) State three risk factors, other than age and sex, that increase a person's chance of developing coronary heart disease. [3]
(d) Discuss how (i) a change in diet and (ii) an increase in exercise could each reduce an employee's risk of developing coronary heart disease. [2]
Question 3
A marine biology student compares the circulatory systems of a bony fish and a mammal.
In the fish, deoxygenated blood is pumped by the heart to the gills, where it becomes oxygenated. This oxygenated blood then flows directly on to the rest of the body, before returning to the heart as deoxygenated blood once again.
In the mammal, deoxygenated blood is pumped by the heart to the lungs, where it becomes oxygenated, and this blood returns to the heart. The heart then pumps the oxygenated blood on to the rest of the body, and deoxygenated blood returns to the heart once more.
(a) State which of these two circulatory patterns is called single circulation, and which is called double circulation. [2]
(b) Explain why the mammal's double circulation delivers oxygen to the body's tissues more efficiently than the fish's single circulation. [2]
(c) In the mammalian heart, the muscular wall of the left ventricle is much thicker than the muscular wall of the right ventricle. Explain why. [2]
Question 4
A patient with kidney failure is connected to a dialysis machine. A tube inserted into a blood vessel in the patient's arm carries blood out to the machine, which removes waste substances from the blood, before a second tube returns the cleaned blood to the same arm. Meanwhile, the patient's own diseased kidneys still receive a blood supply directly from the body's circulatory system.
(a) State two functions of capillaries. [2]
(b) Name the blood vessel that carries blood to the kidney, and the blood vessel that carries blood away from the kidney. [2]
(c) Name the blood vessel that carries blood from the heart to the lungs, and the blood vessel that carries blood from the lungs back to the heart. [2]
(d) State one feature of the structure of a vein that is not found in an artery. [1]
Question 5
A student prepares a stained blood smear and examines it under a microscope, identifying two different types of white blood cell.
- Cell P has a large, round nucleus that almost fills the whole cell.
- Cell Q has a nucleus divided into several lobes, and appears to be surrounding and taking in a small rod-shaped bacterium.
Later, the same student pricks their own finger with a sterile lancet to obtain the blood sample, and notices that the small wound stops bleeding and seals over within a few minutes.
(a) (i) Identify cell P and state its function. [2]
(a) (ii) Identify cell Q and state its function. [2]
(b) Describe the process that seals the finger wound, in terms of the conversion of one protein into another to form a mesh. [3]
(c) State two reasons why this sealing process is important to the body. [2]
Question 6
A student studies gas exchange and transport in a mammal. They read that, in the lungs, a substance inside one type of blood cell combines with oxygen to form a compound called oxyhaemoglobin. This compound then travels around the body in the blood and, in respiring tissues where oxygen concentration is low, releases the oxygen again.
Which component of blood carries out this oxygen-carrying role?
Question 7
A student dissects a mammalian heart in a biology class. After cutting the heart open along its long axis, the student sees four separate internal spaces, flaps of tissue between some of these spaces, and a thick wall of muscle running down the middle of the heart, separating its left and right sides completely.
(a) State the general name given to the two upper chambers of the heart, and the general name given to the two lower chambers. [2]
(b) State the function of the valves found between the atria and the ventricles. [2]
(c) Explain why it is important that the muscular wall between the left and right sides of the heart has no holes in it. [2]
Question 8
A physiology student records an ECG trace and a pressure trace from inside a mammal's left atrium and left ventricle during a single heartbeat, and wants to relate the changes in pressure to the movement of the heart valves.
(a) State what happens to the atria, and to the blood inside them, during atrial contraction. [2]
(b) Describe what happens to the ventricles, and to the atrioventricular and semilunar valves, during ventricular contraction. [3]
(c) Explain why the atrioventricular valves must close before the semilunar valves open during each heartbeat. [2]
Question 9
During an operation, a surgeon needs to identify whether a blood vessel of a certain diameter is an artery or a vein, without being able to observe the direction of blood flow directly. The surgeon instead examines the thickness and composition of the vessel wall and the width of the space inside it.
(a) State two differences between the wall of an artery and the wall of a vein of similar overall diameter. [2]
(b) Explain how the thick wall of muscle and elastic fibres in an artery relates to its function. [2]
(c) Explain how the relatively wide lumen of a vein relates to its function. [2]
Question 10
A medical student labels a diagram of a mammalian heart as part of revision for an anatomy exam, and needs to state the type of blood found in each of the four chambers.
Which row correctly describes the type of blood found in the left atrium and in the left ventricle?