Nerves, synapes, reflexes

• What is the role of the nervous system in homeostasis?


  It detects and reacts to stimuli
• What are the different parts of the nervous system?


  Central nervous system and peripheral nervous system
• What do receptors do in the nervous system?


  They detect stimuli
• What are some examples of receptors in the body?


  Taste receptors on the tongue and sound receptors in the ears
• How do effectors respond to nervous impulses?


  Muscles contract and glands secrete hormones
• What do simple animals rely on for their responses?

  Reflex actions
• What are two types of effectors in the body?


  • Muscles
  • Glands
• What connects neurones in the nervous system?


  Synapses
• How do reflexes help prevent injury?


  They provide quick responses to harmful stimuli
• Through which system does the reflex arc go?


  The Central Nervous System
• What is reaction time?


  • The time it takes to respond to a stimulus
  • Often less than a second
  • Can be affected by age, gender, or drugs
• What is one drug that can speed up reaction time?

  Caffeine
• How can you measure reaction time using a ruler drop test?


  1. Sit with arm resting on a table
  2. Hold a ruler vertically between thumb and forefinger
  3. Let go of the ruler without warning
  4. Catch the ruler as quickly as possible
  5. Repeat and calculate the mean distance fallen
  6. Test after consuming caffeine
  7. Control variables for a fair test
• Why should the person being tested avoid caffeine before the experiment?


  To ensure that the test results are not affected by prior caffeine consumption
• What are the advantages of using a computer to measure reaction time?


  • Provides precise measurements
  • Removes human error from the measurement
  • Records reaction time in milliseconds
  • Prevents anticipation of the stimulus
• How does using a computer test improve the accuracy of reaction time measurements?


  It eliminates human error and records time in milliseconds
• If a student measured their reaction times before and after consuming an energy drink, what should they do with the results?


  Compare the mean reaction times before and after
• What are two variables that should be controlled in the reaction time experiment?


  The same person should catch the ruler and the same hand should be used
• Order of neurones

  Receptors

  Sensory neurone

  Relay neurone ( in spinal chord ) which is a reflex arc , it wouldn't be if it reached the brain

  Motor neurone

  Effector endplate