What is a reflex action? Name the two types of reflexes.
Topic: Reflex action and its types
Answer
A REFLEX ACTION is an automatic, involuntary and rapid response of the body to a stimulus, occurring without the conscious will of the individual and controlled by the spinal cord.
The two types are:
- NATURAL (unconditioned) REFLEXES — inborn and present from birth, such as blinking, sneezing or withdrawing the hand from a hot object.
- ACQUIRED (conditioned) REFLEXES — learnt through repeated experience, such as riding a bicycle, or the mouth watering at the sight of food.
Three marks: the definition, and one for each type with an example.
THE DISTINCTION between the two types is where the marks are: NATURAL reflexes are INBORN — every human has them without learning CONDITIONED reflexes are LEARNT — they must be acquired by repetition, and they can be forgotten
PAVLOV’S EXPERIMENT is the classic illustration of the second and is worth naming: dogs were given food each time a bell rang, and after many repetitions the bell alone made them salivate. A response originally attached to food had been transferred to a sound.
Note that conditioned reflexes involve the BRAIN (the cerebrum forms the new connection), whereas natural reflexes need only the spinal cord.