Biopsychology Flashcards
What is the nervous system?
Main communication system in the body, very fast
What is the nervous system made up of?
A complex network of specialised nerve cells passing messages using chemicals, neurons and neurotransmitters.
What is the CNS made up of?
Brain and spinal cord
What is the function of the CNS?
To pass messages to other parts of the body and receive information from the peripheral nervous system.
What is the spinal cord?
An extension of the brain that is responsible for reflex actions.
What is the PNS ?
Peripheral nervous system
What is the PNS made up of?
Nerve fibres (axons) which are connected to the CNS
What is the function of the PNS?
Sends information to the CNS from the outside world and transmits messages from the CNS to the muscles and glands in the body.
What is the somatic nervous system?
-Controls conscious movement
-Recives instructions from the CNS (motor cortex) for muscle movement
What is the autonomic nervous system?
-Controls unconscious bodily functions like breathing
-Transmits info to and from organs
-Acts more slowly than the SNS
What is the autonomic nervous system made up of?
-Unmyelinated nerve fibres
-Sympathetic and parasympathetic nervous system
What is the somatic nervous system made up of?
Myelinated cells
What is the endocrine system?
Communication system that instructs glamds to release hormones to the bloodstream
Is the endocrine faster or slower than the nervous system?
Slower but still powerful
What is a hormone?
A chemical substance that circulates the bloodstream and affects target organs, produced in large quantities.
What does the hypothalamus do?
Stimulates the release of hormones from the pituitary gland.
What affects do hormones have?
Affects cells in several organs leading to large responses.
What’s the adrenal medulla and its function?
-Produces adrenaline and noradrenaline
-Key role in fight or flight response
What’s the adrenal cortex and its function?
-Produces cortisol
-Triggers the release of glucose to provide the body with energy and suppressing the immune system
What’s the testes and their function?
-Release testosterone
-Responsible for male sex characteristics during puberty and muscle growth.
What’s are the ovaries and their function?
-Release estrogen
-Regulates the female reproductive system, pregnancy and menstrual cycle
What is a neuron?
Nerve cells that are part of the nervous system.
How do they transmit information?
-Electrically through action potentials
-Chemically through neurotransmitters
What do neurons consist of?
Typically a cell body, dendrites and an axon
What are dendrites and what do they do?
They receive information from other neurons, connected to the cell body.
What is the function of the cell body?
Contains all the genetic information of a cell.
What is an axon?
Carries the impulse from the cell body to the terminal.
What is an axon terminal?
The end of the axon, contains neurotransmitters.
What is a myelin sheath?
A fatty coating surrounding the axon, its purpose is to speed up communication.
Function of a sensory neuron
Carries messages from the sense receptors in the PNS to CNS
What size axons and dendrites do sensory neurons have?
Long dendrites and short axons
Do all messages go to the brain?
No, some terminate in the spinal cord to allow reflex actions to occur quickly.
Function of a motor neuron
Connects the CNS to effectors such as muscles and glands.
What size axons and dendrites do motor neurons have?
Short dendrites, long axons
Function of a relay neuron
Connects the sensory neurons to the motor neurons or other relay neurons
What size axons and dendrites do relay neurons have?
Short dendrites, short axons
Where are relay neurons found?
Only in the brain and spinal cord
What is synaptic transmission?
The process in which one neuron communicates with another by releasing neurotransmitters to diffuse across the synapse
What is the synapse?
The gap at the end of one neuron and the dendrite or cell body of another
What is an action potential?
An electrical impulse, charged
What are the 1st and 2nd stages of synaptic transmission?
1) An action potential travels down the axon of the pre synaptic neuron
2) When it reaches the terminal buttons vesicles migrate and bind with the presynaptic membrane, then triggering neurotransmitters
What are the 3rd and 4th stages of synaptic transmission?
3) Neurotransmitters diffuse across the synapse and bind with post synaptic receptors like a lock and key
4) Once activated the receptors produce excitatory or inhibitory effects upon the posy synaptic neuron
What is the 5th stage of synaptic transmission?
5) Neurotransmitters are released back into the synapse and go through reputake or metabolism
What is the function of serotonin?
-To regulate mood (well being and happiness)
-Low levels are associated with depression, OCD and anxiety
What is the function of dopamine?
Pleasure, addiction and motivation
What is the function of GABA?
Has a calming effect
What’s special about GABA ?
Is the only neurotransmitter that’s always inhibitory
What is inhibition ?
-“Off switches”
- A negative charge at the post synaptic membrane creating an inhibitory postsynaptic potential [IPSP]
What is excitation?
-“on switches”
-A positive charge at the post synaptic membrane creating an excitatory postsynaptic potential [EPSP]