Biopsychology Flashcards
What is the nervous system broken down into?
-the CNS and the peripheral nervous system (PNS)
-PNS -> autonomic and the somatic nervous sytem
-Autonomic -> sympathetic and parasympathetic
-Somatic -> sensory (afferent) and motor (efferent)
What is the role of the CNS
It is divided into the brain and the spinal cord. It has two main functions:
1) The control of behaviour
2) The regulation of the bodys physiological processes
What is the role of the spinal cord (CNS)?
Transfers impulses between the brain and the peripheral NS. This allows the brain to monitor and regulate bodily processes such as breathing and digestion. The spinal cord also contains circuits of nerve cells that enable us to perform simple reflexes without the involvement of the brain e.g. pulling hand away from something hot.
The Peripheral nervous system (PNS)
sends info to the CNS from the outside world and transmits messages from the CNS to the muscles and glands in the body.
Subdivided into the:
-autonomic (ANS)
-Somatic (SNS)
The somatic nervous system (SNS)
Transmits info from receptor cells in the sense organs to the CNS. It also recieves info from the CNS that directs muscles to act. It is responsible for voluntary muscle movements. Connects the CNS and the senses, recieves impulses from the senses. It also directs muscles to act and move.
The autonomic nervous system (ANS)
Responsible for unconcious bodily functions e.g. breathing and digestion. Transmits and recieves impulses from from the organs and is subdivided into the:
-Sympathetic NS
-Parasympathetic NS
The sympathetic NS
Involved inresponses that help us respond in emergencies (fight/fight). It signals our heart and lungs to work harder and our liver to release glucose (when our muscles need energy and oxygen). Coordinates organs in situations that require individual to be aroused and expend energy.
The parasympathetic NS
Coordinates organs when we can relax and conserve energy. It promotes digestion and slows our heart and breathing. (rest and digest)
What are four things that happen when the sympathetic NS is active?
-DIlates pupils (to see better)
-Increases heart rate
-Dilates bronchi
-Directs blood to muscles
Describe the structure and function of a neurone (6)
-nucleus contains the genetic material of the cell
-Axon carry messages away from the cell
-dendrites carry functional information towards the cellbody
-dendrites can recieve info from other neurones
-Myelin sheath insulates the axon so that the electrical impulses travel faster along the axon
-axon terminals contain neurotransmitters
Motor neuron
carry impulses from the CNS to other areas of the body and control muscles. When stimulated, release neurotransmitters that bind to the receptors on the muscle and trigger muscle movement.
Relay neuron
Lie inbetween the sensory and motor neuron and connect the sensory and relay neuron, they are found solely within the brain and spinal cord
Sensory neuron
Transmit nerve impulses from the sensory receptors to the brain and spinal cord.
Define synaptic transmission
The process of transmitting impulses from neuron to neuron
The synaptic transmission process
- electrical impulses (action potential) reach the presynaptic terminal
-Electricalimpulses trigger release of neurotransmitters
-Neurotransmitters (nts) cross the synapse from vesicles
-nts combine with receptors on the post synaptic membrane
-stimulation of postsynaptic receptors by nts result in either excitation (depolarisation) or inhibition (hyperpolarisation) of the postsynaptic membrane
excitatory neurotransmitters
Increase the positive charge of the post-synaptic neuron. This increases the likelihood that the neuron will fire and pass on the electrical impulse.
Inhibitory neurotransmitters
Increase the negative charge of the post-synaptic neuron. This decreases the likelihood that the neuron will fire and pass on the electrical impulse
What is summation?
The excitatory and inhibitory influences are summed, if the net effect on the post-synaptic neuron is inhibitory, the neuron will be less likely to fire and if the net effect is excitatory, the neuron will be more likely to fire.
what do you need to include for this question:
Briefly outline how excitation and inhibition are involved in synaptic transmission (4Marks)
-excitatory and inhibitory neurotransmitters and their effects (2)
-‘Neurotransmitters can be excitatory or inhibitory (most can be both, but GABA is purely inhibitor) (1)
-summation (1)
define the endocrine system
One of our body’s major information systems that instructs glands to release hormones directly into the bloodstream. These hormones are carried towards target organs in the body.
-helps regulate and the activity of cells and organs in the body
How does the nervous system and endocrine system differ?
Hormones are released through blood vessels whereas, neurotransmitters are released through a network of neurons
The process of hormones being secreted
- endocrine glands secrete hormones directly into the bloodstream in response to a signal from the brain
-Hormones travel to their ‘target cells’ and exert their influence by stimulating the receptors on the surface or inside the cells
-The presence of a hormone causes a physiological reaction in the cell which alters its activity - Each hormone affects behaviour in a different way
Pituitary gland
-produces hormones that regulate the endocrine system ‘master gland’
-influences the release of hormones from other glands
-releases ACTH which plays a large role in how our bodies respond to stress
-The release of ACTH triggers the adrenal gland to produce cortisol, the “stress hormone”
Adrenal gland
An important part of the ‘fight or flight’ response as it secretes the release of adrenaline