B6 Flashcards
What is the nervous system made up of ? give examples
They are made up of neurons (nerve cells) linking receptors cells(e.g in eyes ,ears and skin) to effector (in muscles/glands)
When stimulated, neurons transmit what?
An electrical pluse
Describe axon
It is a long extension of the cytoplasm in a neuron and is surrounded by a cell membrane
What are some axon surround by a fatty sheath ?
The fatty (or myelin) sheath insulates the neuron from neighbouring cells and increasing the speed of transmission of a nerve impulse.
What does PNS stand for and what is made up of/
The Peripheral Nervous System. It is made up of the sensory and motor neurons.
The CNS coordinates an animal responses using two neurons in the PNS. What are these called and what do they do?
The sensory and motor neurons.The sensory neurons carry impulses from receptors to the CNS (the relay neurons in the CNS). The motor neurons carry impulses from the CNS to the effectors
In the CNS how are impulses passed from sensory to motor neurons?
Through the relay neurons
Why is beneficial to have an arrangement of neutrons in a fixed pathway?
To allow reflex responses to be automatic and so very rapid , since no processing of information is required
Explain how a synapse works
At a synapse, an impulse arriving triggers the release of chemicals ( transmitted substances) from the first neuron into the synapse. These chemicals diffuse across the synapse and bind to the receptor molecules on the membrane of the next neuron. Only specific chemical bind to the receptors molecules and initiates a nerve impulse in the next neuron
Identify 3 drugs that can affect the transmission of impulses across a synapse.
ECSTASY, BETA BLOCKER, AND PROZAC
Explain how ecstasy affects the synapses
Ecstasy (MDMA) blocks the sites in brains synapses where the transmitted substances , serotonin, is removed.This means there is an increase in serotonin concentration in the body
What is the cerebral cortex in our brain most concerned with?
Intelligence, memory, language, and consciousness
How can scientists map the regions of the brain to particular functions.
Using studies of patients with brain damage, studies in which different parts of the brain are stimulated and brain scans such as MRI ( showing brain structure and activity)
