biopsychology Flashcards
What is the nervous system (1)
A network of cells in the human body, the body’s internal communication system
What is the function of the nervous system (2)
To collect, process and respond to information from the environment (1) and to control organs and cells in the body (1)
The nervous system is broken down into
Central nervous system and the peripheral nervous system
What is the function of the peripheral nervous system
Sends messages to and from the central nervous system via neurons
What is the central nervous system split into
Brain and spinal cord
What is the peripheral nervous system spilt into
Autonomic nervous system and somatic nervous system
What is the autonomic nervous system broken down into
The sympathetic branch and the parasympathetic branch
What is the function of the sympathetic branch
Flight or fight response
What is the function of the parasympathetic branch
Converse and restore body energy when relaxed
What is the role of the brain (6)
Receives and processes information from the senses e.g. visual cortex processes visual info.
The centre of conscious awareness
Responsible for higher mental functions
Generates emotion and thoughts
Initiates responses
Stores memories
What is the role of the spinal cord
Conducts signals (sends messages) to and from the brain
Connects nerves to the PNS
Controls reflex actions e.g.
removing a hand when it touches a hot plate
What is the role or the Autonomic nervous system
Responsible for involuntary responses for vital functions e.g. breathing, digestion and the stress response, heart rate
Controls smooth and cardiac muscles and glands
ANS control centres are in the brain stem.
What is the role of the somatic nervous system
Responsible for voluntary movements such as walking
Transmits information from the brain or the skeletal muscles
SNS carries commands from (controlled by) the motor cortex
Connects the CNS and the senses and integrates the brain with the outside world
Describe two differences between the autonomic nervous system and the somatic nervous system
Responsible for involuntary responses for vital functions e.g. breathing, digestion and the stress response, heart rate
Where as
Responsible for voluntary movement such as walking
Controls smooth and cardiac muscles and glands
Where as
Transmits information from the brain to control skeletal muscles
ANS control centres are in the brain stem.
Where as
SNS carries commands from (controlled by) the motor cortex
What is the structure of a neuron
- Terminal button (pre-synaptic membrane)
- Dendrites (Post synaptic membrane)
- Cell body
- Axon
- Myelin sheath
- Nodes of ranvier (the gap)
What is the terminal button (pre-synaptic membrane)
The end of the neuron and they send the information through to the next neuron, through the release of neurotransmitters.
What are dendrites (post-synaptic membrane)
These are where the neurotransmitter receptors are found. Once the receptor and neurotransmitter bind, this causes a new electrical impulse to occur.
What is the cell body
Includes the nucleus which contains the genetic material of the cell
What is the axon
Sends a nerve impulse (action potential) through the neuron to transmit a message to the
next neuron
What is the myelin sheath
Protect the axon and helps to speed up transmission of the message
What is the node of ranvier
Speeds up the transmission of the impulse by forcing it to ‘jump’ across the gaps along the axon
Where is the location of a sensory neuron
The PNS in clusters known as ganglia
What is the function of the sensory neuron
These send information from the senses (PNS) towards the brain (CNS).
Receptors found in eyes, ears, tongue, skin.
What is the structure of the sensory neuron
They have long dendrites and short axons.
What is the location of a relay neuron
In the brain and the visual system
What is the function of a relay neuron
Relay neurons are found in the CNS (brain/visual system/spinal cord).
They carry nerve impulses between neurons allowing sensory and motor neurons to communicate.
They are involved in analysing the sensations from these neurons and deciding how to respond.
What is the structure of a relay neuron
They have short dendrites and short axons, and no myelin sheath.
What is the location of a motor neuron
Cell bodies are found in the CNS but the long axons form part of the PNS
What is the function of a motor neuron
These send information via long axons from the brain/spinal cord (CNS) through to effectors such as muscles or glands.
What is the structure of a motor neuron
They have short dendrites and long axons
Describe the process of synaptic transmission
- The process of synaptic transmission begins in the presynaptic neuron, action potentials (electrical nerve impulses) are sent down the axon until they reach the presynaptic terminal
- This causes the neurotransmitters (chemicals), which are stored in vesicles and are ONLY located in the presynaptic neuron, to be released into the synaptic cleft (the gap between each neuron)
- These neurotransmitters diffuse across the synapse (from high to low concentration) and then bind with their specific receptor sites that are ONLY present on the postsynaptic neuron (like a key into a lock)
- Once enough neurotransmitters have attached to the receptor sites on the post synaptic neuron, there are two possible outcomes:
The next neuron is ready to fire an impulse, depending on whether the neurotransmitter has an excitatory or inhibitory effect.
OR
The neurotransmitters are recycled to be stored back in the vesicles in the presynaptic neuron in a process called reuptake.
What are neurotransmitters
There are chemical messengers within the brain
What is the role of a neurotransmitter
Their role is to transmit information from one neuron to another so that a person performs an action e.g. movement or has an emotional response.
Define excitatory neurotransmitter (3)
Give an example
When the excitatory neurotransmitter binds to the post synaptic receptors - post synaptic cell (the next neuron) becomes positively charged (1)
This will make it more likely that the post synaptic cell will fire so an impulse will travel down its axon (2’
This increases the brain activity in the central nervous system (3)
E.g adrenaline
Define inhibitory neurotransmitter (3)
Give an example
When the inhibitory neurotransmitter binds to the post synaptic receptors the post synaptic cell (next neuron) becomes negatively charged (1)
This prevents or reduced the likelihood that the post synaptic cell will fire (2)
This decreases brain activity in the central nervous system (3)
E.g Serotonin
Define summation (3)
Summation occurs when the excitatory and inhibitory influences are added together (1)
If the overall effect is mainly inhibitory (negatively charged) it reduces the likelihood the neuron will fire an impulse down the post synaptic neuron (2)
If it is mainly excitatory (positively charged) the impulse will fire an impulse down the post synaptic neuron (3)
What is the function of the endocrine system
The endocrine system provides a chemical system of communication within the blood stream to regulate the activity of cells and organs in the body
It is slower than the nervous system but its effects are more widespread and powerful.
These chemical messengers are hormones, which are released by the glands within the endocrine system to regulate many bodily functions.
What are hormones
Chemical messengers which are released by the glands within the endocrine system to regulate many bodily functions
such as melatonin and oestrogen
The role of glands in the endocrine system - what is a gland
A gland is an organ that secretes hormones that regulate functions in the body.
Name 4 glands (need 2 in the exam at least )
Pineal gland
Adrenal gland
Pituitary gland
Ovaries
Testes
The role of the pineal gland
Secretes the hormone melatonin, which is involved in regulating the sleep-wake cycle by making the person feel tired and therefore ready to sleep
The role of the adrenal gland
Releases adrenaline which causes physiological changes involved in the fight or flight response such as increased blood flow to transport oxygen to the brain for rapid response planning.