the human nervous system Flashcards
(19 cards)
What is a stimulus?
A detectable change in the internal or external environment.
What is a receptor?
A structure that detects a stimulus and converts it into an impulse.
What is an impulse?
An electrical signal created by a receptor in response to a stimulus.
What is an effector?
A gland or organ that carries out a response to a stimulus.
What are the two co-ordinating systems in humans?
The nervous system and the endocrine system.
How do the nervous and endocrine systems differ?
The nervous system responds quickly using nerves; the endocrine system responds slowly using hormones.
What are the two main parts of the nervous system?
The central nervous system (CNS) and the peripheral nervous system (PNS).
What does the CNS consist of?
The brain and spinal cord.
What does the PNS consist of?
Cranial and spinal nerves; includes the somatic and autonomic systems.
What is the autonomic nervous system?
Controls involuntary actions like heartbeat and digestion.
What are the two parts of the autonomic system?
Sympathetic (speeds up functions) and parasympathetic (slows down functions).
What is a voluntary action?
An action under conscious control, like walking or eating.
What is an involuntary action?
An automatic response, like sneezing or breathing.
What is homeostasis?
Maintaining a stable internal environment despite external changes.
What is the function of the meninges and cerebrospinal fluid?
To protect the brain and spinal cord.
What is a neuron?
A specialized nerve cell that transmits impulses.
What is a synapse?
A gap between neurons where impulses are passed using neurotransmitters.
What is Alzheimer’s disease?
A nerve disorder in older people causing memory loss and confusion.
What is multiple sclerosis?
A disease caused by damage to the myelin sheath of neurons.
