Paper 1 - The Nervous System Flashcards
What does the human nervous system consist of?
Central nervous system (CNS)
Peripheral nervous system (PNS)
What does the central nervous system consist of?
Brain and spinal cord
What is an axon
The long part of a nerve cell along which the electrical signal quickly moves.
what is a cell membrane
A selectively permeable membrane surrounding the cell and controlling the entry and exit of materials.
what is an effector
give example
The organ, tissue or cell that produces a response.
Effectors include muscles and glands. They produce a specific response to a detected stimulus. For example:
a muscle contracting to move an arm
muscle squeezing saliva from the salivary gland
a gland releasing a hormone into the blood.
what is a neurone
Nerve cells. They carry an electrical message or impulse when stimulated.
What is a neurotransmitter
Chemical involved in passing nerve impulses from one nerve cell to the next across a synapse.
what is a receptor
Organs which recognise and respond to stimuli. Receptors are groups of specialised cells. They detect a change in the environment and stimulate electrical impulses in response. Sense organs contain groups of receptors that respond to specific stimuli.
what is a stimulus
Something that sets off a reaction in the nervous system, for example, light, heat, sound, gravity, smell, taste, or temperature. These changes in the environment are detected by receptors in an organism. The plural is stimuli.
what is a synapse
A tiny gap at the junction between two nerve cells, which nerve signals must cross.
Describe how information flows from receptor to effector in the nervous system
stimultus
receptor
coordinator (brain, spinal cord or pancreas)
effector
response
what are the three types of neurone
sensory
motor
relay
what is an Axon?
The long part of a nerve cell along which the electrical signal quickly moves.
summarise how information flows from receptors to effectors in the central nervous system
What is the role of the brain and the spinal cord as part of the nervous system ?
It receives information from receptors and coordinates a response which is carried out by effectors
