Biopsychology L1-5 Flashcards
What is the central nervous system?
consists of the brain and spinal cord.
Two main functions:
- control of behaviour.
- regulation of body’s physiological processes.
To do this the brain must be able to receive info from sensory receptors and be able to send messages to muscles and glands in response.
What are the 4 areas of the brain?
- Cerebrum - largest part. Has four lobes and is split down the middle into 2 parts called hemispheres.
- Cerebellum- responsible for motor skills, balance and coordinating muscles for precise movements.
- Diencephalon- contains thalamus and hypothalamus.
- Brain stem- regulates breathing and heart rate.
What does the thalamus and hypothalamus regulate?
Thalamus- consciousness, sleep, alertness.
Hypothalamus- body temp, hunger/thirst, stress response.
What is the function of the spinal cord?
Main function is to relay information between the brain and rest of the body.
- allows brain to monitor/regulate bodily processes like digestion and breathing.
- is connected to different parts of body by pairs of spinal nerves.
- if it is damaged, body areas connected to it by nerves below the damage will be cut off and stop functioning.
What is the peripheral nervous system?
- consists of the nervous system throughout the rest of the body.
- the PNS transmits messages via neurons to and from the CNS.
Has 2 divisions: - somatic nervous system.
- autonomic nervous system.
What is the somatic nervous system?
Controls voluntary movements.
- is under conscious control.
- connects the senses with the CNS.
- has sensory and motor pathways.
- controls skeletal muscles.
- controlled by the motor cortex.
What is the autonomic nervous system?
- not under conscious control.
- only has motor pathways.
- controls smooth muscle, internal organs and glands.
- controlled by the brain stem.
What are the 2 part of the autonomic nervous system?
- Sympathetic nervous system- activated under stress (fight/flight response). Heart rate and breathing increases, digestion stops, pupils dilate, salivation stops, flow of blood diverted from skin surface.
- Parasympathetic nervous system- activated under relaxation. Conserves energy. Heart rate and breathing reduced. Digestion starts, salivation increases, pupils constrict.
What are neurons?
Specialised nerve cells that move electrical impulses to and from the central nervous system.
What is the role of the cell body, nucleus, dendrites and axon of a neuron?
- Cell body- control centre of neuron.
- Nucleus- contains genetic material.
- Dendrites- receives electrical impulse from other neurons/ sensory receptors.
- Axon- a long fibre that carries electrical impulse from the cell body to the axon terminal.
What is the structure of a neuron?
- cell body
- nucleus
- dendrites
- axon
- myelin sheath
- schwann cells
- nodes of ranvier
Role of myelin sheath, schwann cells, nodes of ranvier in neurons?
- Myelin sheath- insulting layer that protects the axon and speeds up transmission of the electrical impulse.
- Schwann cells- make up myelin sheath.
- Nodes of ranvier- gaps in myelin sheath. Speed up electrical impulse along axon.
Sensory neuron. Function/location/structure?
- found in sensory receptors.
- convert information from sensory receptors into electrical impulses and carry them from the receptors to the CNS via the PNS.
- when reached the brain, converted into sensations (eg. Pain).
- some impulses terminate at spinal cord. Allowing reflexes to occur quickly. (Don’t have to go to brain)
- have long axon. Cell body located in middle.
Motor neuron. Function, structure, location?
- located in CNS, however project their axon outside of cns.
- send electrical impulses via long axons to the glands and muscles (effectors) so they can affect function.
- once stimulated, they release neurotransmitters that bind to receptors on muscles to trigger a response.
Relay neuron. Function/location/structure?
- found in the CNS.
- connect sensory neurons to motor neurons so that can communicate with each other.
- during reflex arc, the relay neurons in spinal code analyse the sensation and decide response without waiting for brain to process it.
- short axon. No myelin sheath.
