Unit 1 Exam Flashcards
Central nervous system consists of
Brain and spinal cord
Peripheral nervous system consists of
Somatic and autonomic
Role of autonomic
Sympathetic and parasympat hetic
Somatic NS
Carries sensory information received from sensory receptor cells to CNS via sensory neurons.
- Voluntary skeletal muscle movement
Autonomic NS
Carries messages from the brain to internal glans and organs via motor neurons.
- Involuntary skeletal muscle movement
Sympathetic NS
Controls fight or flight response
Parasympathetic NS
Controls rest and digest response
Sympathetic NS body parts affected
- Pupils dilate
- Saliva production inhibited
- Heart rate increases
- Digestion is inhibited
Parasympathetic NS body parts affected
- Pupils constrict
- Saliva production stimulated
- Heart rate decreases
- Digestion is stimulated
Structure of neuron
- Dendrites
- Soma/cell body
- Axon
- Axon terminals
- Myelin sheath
Neuron
Cells of the nervous system that communicate with each other
Dendrites
Extensions of the cell body that receive neurotransmitters from pre-synaptic neurons.
Soma/cell body
Contains a nucleus that controls the activities of the neuron
Axon
The long projection of a neuron that conducts electrical nerve impulses.
Axon terminals
The enlarged end points of axon branches that store neurotransmitters.
Myelin sheath
Fatty covering of the axon that acts as an insulator.
Sensory neurons
Process sensory information and carry messages to spinal cord and brain. (Afferent)
Motor neurons
Carry motor messages from the spinal cord and brain to muscles. (Efferent)
Interneurons
Act as the connection between sensory neurons and motor neurons.
Neurotransmitters
Molecules found within the nervous system that act as chemical messengers.
Role of neurotransmitters
Allow neurons to communicate by relaying information between them across the synapse.
Role of the synapse
Connect neurons and help transmit information from one neuron to the next
Electro chemical signal
Explained as an electrical nerve impulse (action potential) travels through the neuron and neurotransmitters.
Direction of transmission
Travels in one direction only from the dendrites to the cell body, then along the axon to the axon terminals.
Hindbrain
- Coordinates sensory and motor messages
- Medulla and Cerebellum
Midbrain
Receives sensory messages from all the senses except smell and sends information to the forebrain
- Reticular formation
Forebrain
Largest part of the brain that plays a key role in cognition, emotion, behaviour and processing sensory information
- Thalamus, Hypothalamus
Medulla
Lowest part of the brainstem that relays information between spinal cord and brain.
- Regulates the respiratory and cardiovascular system
Cerebellum
Convoluted structure at the back of the brain
- Involved in balance, judging distance, and coordination of motor movement
Reticular formation
Network of nuclei located within the length of the brainstem.
-Helps maintain wakefulness and alertness (sleep cycle)
Thalamus
Double-lobed structure located above brainstem, that receives sensory information except smell.
Hypothalamus
Structure that sits below thalamus and regulates sleep, eating, body temp and sexual drive.
Cerebral cortex
Outermost layer of the brain made up of nerve cell tissue.
- Responsible for higher order processes (memory, language reasoning etc)
Left hemisphere
- Controls movement of the right side of the body
- Language and logical reasoning
Right hemisphere
- Controls movement of the left side of the body
- Creativity and imagination
Corpus callosum
Thick band of nerve fibres (white matter) connecting both hemispheres of the brain.
White matter
Consists of myelinated axons.
Grey matter
Consists of unmyelinated axons