Transport in animals

Traps in Transport in animals

• Reverses a direction, order or effect
  Before answering, say the process out loud in order with arrows (receptor → sensory → relay → motor → effector; lungs → pulmonary vein → left atrium). Then ask: does my option point the same way? If an option is the mirror image of a fact you know, it is a trap.
• Gives the job of a neighbouring structure or stage
  Learn structures as pairs of 'name → one job' and contrast neighbours: ribosome makes protein, mitochondrion releases energy; cochlea hears, semicircular canals balance. When two options sit in the same organ or process, ask which one does exactly the job in the stem.
• Uses an everyday idea instead of the biology
  Translate everyday words into the textbook definition before choosing. If the only reason an option attracts you is its name or looks, test it against the definition in the stem.
• Mixes up a pair of similar technical terms
  Make a two-column table for each confusable pair with one defining feature each, and a memory hook (aTLas holds the 'world' (skull) and nods; aXis lets you shake 'no'). Underline the defining feature the stem gives before you look at the options.
• Classifies vessels by oxygen, not direction
  Arteries carry blood Away from the heart; veins carry it towards the heart. Pulmonary vessels are the exception for oxygen, not for direction.
• Mixes up blood cell functions
  Red cells (no nucleus, haemoglobin) carry O₂; white cells defend (phagocytes engulf, lymphocytes make antibodies); platelets help clotting.
• Takes one contributing factor as the whole answer
  Watch for 'only', 'just', 'mainly'. Ask: is this the MAIN reason, or one contributor? If it would need other things to work (plasma proteins need platelets), it is incomplete.
• Chooses a true but irrelevant statement
  Re-read the question word (why, which, where, what causes). An option can be a true fact and still be wrong because it answers a different question.
• Over-generalises a rule to all cases
  Absolute words (all, always, every, never) are rarely right in biology. Try to name one exception; if you can, reject the option.
• Puts an example in the wrong group
  Classify by the defining features in the key, not by habitat or name: mammals have hair and mammary glands; true fruits come from the ovary only. Check each option against the defining feature in turn.