Nervous System & Homeostasis Flashcards
(18 cards)
What is the function of the nervous system?
Enables humans to react to their surroundings and coordinate behaviour (voluntary and involuntary actions).
What is the structure of the nervous system?
Made up of the central nervous system (CNS) and a network of nerves. The CNS includes the brain and spinal cord.
What are the stages of nervous system response?
Stimulus → Receptor → Coordinator → Effector → Response.
What is a stimulus?
A change in the environment detected by receptors.
What do receptors do?
Pass information to the CNS via neurones as electrical impulses.
What does the CNS do in response to a stimulus?
Coordinates the body’s response.
What is the role of effectors?
Muscles or glands that produce a response (e.g., contracting or secreting hormones).
What is homeostasis?
Regulation of internal conditions to maintain optimum conditions for cell function and enzyme action.
What does homeostasis control in the body?
Blood glucose, body temperature, and water levels.
What are the components of homeostasis control systems?
Receptor cells, coordination centres, and effectors.
What factors affect human reaction time?
Tiredness, distractions, and caffeine.
What are reflex actions?
Automatic, rapid responses that don’t involve the conscious brain and help prevent body damage.
What is a reflex arc?
Pathway of reflex: stimulus → sensory neurone → relay neurone → motor neurone → effector.
What do sensory neurones do?
Carry electrical impulses from receptors to the CNS.
What do motor neurones do?
Carry impulses from the CNS to effectors.
What is a synapse?
A gap between neurones where chemicals transfer signals.
How do synapses work?
Chemicals released from one neurone cross the synapse and trigger a new impulse in the next neurone.
What is the role of relay neurones?
Connect sensory neurones to motor neurones within the CNS.
