Biology Year 8 Flashcards
Central Nervous System
Part of the nervous system consisting of the brain and spinal cord
Peripheral Nervous System
Connects the Central Nervous System to the rest of the body
Neurons
Nerve cells
Nerve
Made up of neurons
Sensory Neurons
Sends messages to the Central Nervous System
Interneurons
Carries the impulse through the Central Nervous System
Motor Neurons
Takes messages away from the Central Nervous System
Nucleus
Central part of the atom made up of protons and neutrons
Organelles
Small structure in the cell
Cytosol
Fluid inside a cell
Cell membrane
Encloses the content of the cell and allows things to go through and not go through
Cell body
Contains the nucleus of a neuron and also called grey matter
Dendrites
Relays information to the cell body
Axon
Appendage of the neuron. Nerve impulses travel along this
Myelin
White substance that encases the axons
Synapse
Gap between neurons
Vesicles
A small cavity filled with fluid
Neurotransmitter
Chemical released from axon terminals into the synapse
Effector
An organ that responds to the stimulus
Reflex arc
A pathway involving a small number of neurons.
The impulses travel from the receptors to the spinal cord and than to the effector organ
Conscious response
An action or response done knowingly and consciously
E.g. Your friend waves at you and you say hi. This is done consciously as you don’t have to wave back. This means you do it knowingly and the action can be preventable
