Biopsychology Flashcards
What is the nervous system?
A specialised network of cells and our primary communication system
What is the nervous systems 2 main functions
To collect, process and responded information in the environment
To coordinate the working of different organs and cells in the body
What is the central nervous system?
It is made up of the brain and spinal cord
The brain is the centre of all consciousness awareness
The cerebral cortex of the brain = higher mental functions.
The spinal cord is an extension and is responsible for reflex actions
It passes messages to and from the brain and connects nerves to the PNS.
What is the structure of the PNS
Sub divided into into the autonomic and somatic
Autonomic governs vital functions in the body such as heart rate and breathing
The somatic controls muscle movement and receives information from sensory receptors.
The autonomic breaks off into the sympathetic and para sympathetic
What does the endocrine system do?
It controls vital functions through the use of hormones
It is slower than the CNS
What are glands function in the endocrine system
Glands are organs in the body that produce hormones
Putitry gland controls all other glands and is located in the brain
What is the hormones job in the endocrine system?
Hormones are secreted into the blood stream and affect any cell in the body that has a receptor for that particular hormone
Thyroxine produced by the thyroid effects cells in the heart and in the body that increase metabolic rate this effects growth hormones.
What is the flight or fight response?
Stress Hypothalamus Sympathetic branch Adrenaline Increased Hr and dilation of pupils Threat passes Parasympathetic branch Rest and digest
What are neurons
They work by transmitting signals electrically and chemically these provide the nervous system with the primary means of communication
Motor neurons
Sensory neurons
Relay neurons
What are motor neurons
They connect the CNS to effectors such as muscles and glands. They have short dendrites and long axons
What are sensory neurons
They carry messages from the PNS to the CNS they have long dendrites and short axons
What are relay neurons
They connect sensory to motor or other relay. They have short dendrites and short axons.
What is teh structure of the neuron
Cell body - genetic material of the cell
Dendrites- branch like structure that protrude from the cell body. These carry nerve impulses from neighbouring neurons to the cell body.
Axon - carries electrical signals away from the cell body it is covered in a fatty layer called the myelin sheath. Gaps in the axon called nodes of ravienier speed up transmission of the impulse.
Terminal buttons - at the end of the axon communicate with the next neuron in the chain across a gap called a synapse
What happens in electric transmission
When a neuron is in resting state the inside is negatively charged.
When a neuron is activated, the inside of the cell becomes positively charged for a split second causing an action potential to occur
It creates an electrical impulse to travel down the axon towards the end of the neuron.
What is a synapse
Each neuron is separated from the next by a gap
What is a chemical transmission
Signals between neurons are transmitted chemically across the synapse.
When the electrical impulse reaches the end of the neuron it triggers the release of neurotransmitter from the synaptic vesicles. It travels the gap and then is taken up by the post synaptic transmitters
The chemical message is then turned back into electrical impulses
What are neurotransmitters
They are chemicals that diffuse across the synapse to the next neuron
They each have their own specific molecular structure that fits perfectly into the post synaptic receptor.
E.g seretonin
What is excitation and inhibition?
Excitation - more positive charges, making the neuron willing to fire. E.g adrenaline
Serotonin - increases negative charge making it less likely to fire e.g seretonin
