Transport in Animals | OCR A-Level Biology A (H420)
Transport in Animals
- 103 questions
- 8 subtopics
- Module 3: Exchange and transport
- Component 01 and Component 03
Transport in animals is the second section of Module 3.
It covers single and double circulation, the structure of arteries, veins and capillaries, how tissue fluid forms and returns, the mammalian heart and the cardiac cycle, the electrocardiogram, and how blood carries oxygen and carbon dioxide.
Sample questions from Transport in Animals
Answer each one closed book first, then open the answer.
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Why animals need transport systems
What defines a single circulatory system?
Show the answer
Blood passes through the heart once per complete circuit of the body. -
Arteries, veins and capillaries
How do arterioles differ from arteries in terms of smooth muscle, and what does this allow?
Show the answer
Arterioles have relatively more smooth muscle than arteries, allowing vasoconstriction and vasodilation to control blood flow to tissues. -
Tissue fluid and lymph
What is the net direction of fluid movement at the arterial end of a capillary, and why?
Show the answer
Net outward movement occurs because hydrostatic pressure exceeds oncotic pressure, forming tissue fluid. -
The structure of the mammalian heart
Which vessels return oxygenated blood from the lungs to the heart?
Show the answer
The pulmonary veins. -
The cardiac cycle and control of the heartbeat
What causes the semilunar valves to close?
Show the answer
They close when arterial pressure exceeds ventricular pressure, preventing backflow into the ventricles. -
The electrocardiogram
What does the T wave on an ECG represent?
Show the answer
Ventricular repolarisation (recovery of the ventricles). -
Transporting oxygen and carbon dioxide
Explain what is meant by cooperative binding in haemoglobin.
Show the answer
Binding of the first oxygen molecule causes a conformational change that increases the affinity of haemoglobin for subsequent oxygen molecules. -
Oxygen dissociation curves and the Bohr effect
Why is it advantageous for fetal haemoglobin to have a higher oxygen affinity than adult haemoglobin?
Show the answer
It allows the fetus to obtain oxygen from maternal blood across the placenta, where oxygen partial pressure is relatively low.
The 8 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Why animals need transport systems | Size, metabolic rate and surface area to volume ratio, and the difference between single and double, open and closed circulatory systems. | 12 |
| Arteries, veins and capillaries | Wall structure, lumen size, valves and the amount of elastic and muscle tissue in each vessel, and how each one suits the pressure it carries. | 16 |
| Tissue fluid and lymph | Hydrostatic and oncotic pressure at each end of a capillary, how tissue fluid forms and returns, and how plasma, tissue fluid and lymph differ. | 10 |
| The structure of the mammalian heart | The four chambers and the vessels entering and leaving them, the valves, chordae tendineae and papillary muscles, and why the left ventricle wall is thicker. | 16 |
| The cardiac cycle and control of the heartbeat | Atrial systole, ventricular systole and diastole, what opens and closes the valves, the cardiac output calculation, and the route from sino-atrial node to Purkyne tissue. | 15 |
| The electrocardiogram | What the P wave, QRS complex and T wave represent, and how tachycardia, bradycardia, fibrillation and an ectopic beat appear on a trace. | 11 |
| Transporting oxygen and carbon dioxide | The quaternary structure of haemoglobin and cooperative binding, and the three ways carbon dioxide travels, including carbonic anhydrase and the chloride shift. | 13 |
| Oxygen dissociation curves and the Bohr effect | Why the curve is sigmoid, how fetal haemoglobin differs from adult haemoglobin, and the shift the Bohr effect produces and what it achieves in respiring tissue. | 10 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby sections
OCR A-Level Biology A Active Recall Guide
Every section, not just this one. 1,833 questions with their answers.