How to Revise Transport in animals — OCR A-Level Biology
Transport in animals is a topic in the OCR A-Level Biology specification. This guide covers learning objectives, examiner tips, common mistakes, and key terminology to help you revise effectively.
Examiner Tips for Transport in animals
- Ensure you can link the structure of blood vessels to their specific functions
- Practice calculating cardiac output using the formula: cardiac output = heart rate x stroke volume
- Be prepared to interpret ECG traces for specific heart conditions
- Understand the significance of the shift in the oxygen dissociation curve for fetal haemoglobin
- Use precise terminology when describing the chloride shift
Common Mistakes in Transport in animals
- Confusing hydrostatic and oncotic pressure in tissue fluid formation
- Incorrectly describing the sequence of the cardiac cycle
- Failing to mention the myogenic nature of cardiac muscle
- Misinterpreting the Bohr effect on the oxygen dissociation curve
- Confusing the roles of the SAN and AVN
Key Marking Points
- Need for transport systems related to SA:V ratio and metabolic rate
- Differences between single, double, open, and closed circulatory systems
- Structural differences between arteries, arterioles, capillaries, venules, and veins
- Formation of tissue fluid from plasma via hydrostatic and oncotic pressure
- Cardiac cycle stages and pressure changes
- Initiation and coordination of heart action (SAN, AVN, Purkyne tissue)