Lecture 9 Flashcards
What is the Synaptic Cleft?
A gap between the axon terminal of one neuron and the dendrite of the next, where synaptic transmission occurs
How does communication between neurons work?
Neurotransmitters are transported through the synaptic cleft (this is known as neurotransmission)
What are Neurotransmitters?
Chemical messengers which typically work by exciting or inhibiting neurons
What are the 5 stages of Neurotransmission?
Synthesis Storage Release Binding Deactivation
What is Synthesis in Neurotransmission?
Formation in the neuron
Where is Storage of neurotransmitters in Neurotransmission?
In synaptic vessels
Where do neurotransmitters get released?
Between the presynaptic neuron and the postsynaptic neuron
Where do Neurotransmitter bind to?
The receptor sites (large protein molecules)
What is Deactivation of neurons?
Via chemical breakdown or reuptake
What happens during reuptake of Neurotransmitters?
Chemicals are reabsorbed into the presynaptic neuron
What is another way that neurotransmitters are deactivated?
They undergo chemical breakdown in the synapse
How do excitation neurotransmitters work?
They stimulate the flow of positively charged ions into a neuron (excitation) which makes it easier to fire an action potential
How do inhibition neurotransmitters work?
They stimulate the flow of positively charged ions (K+) out of the cell or negatively charged ions (Cl-) into the cell. This decreases the membrane potential which creates a hyperpolarized state
What are Neuromodulators?
Neurotransmitters that have widespread effects
What are the Characteristics of Glutamate?
- Primary excitatory neurotransmitter.
* Important for learning, memory
What is GABA?
- Primary inhibitory neurotransmitter
* Important for motor control, anxiety
What occurs in Huntington’s disease?
Destruction of GABA producing neurons which leads to tremors and loss of motor control
What is Acetylcholine (ACh)?
An excitatory neurotransmitter involved in memory, muscle activity
What occurs in Botulism?
A type of food poisoning in which bacteria block the release of ACh and causes paralysis
What can underproduction of Acetylcholine be associated with?
Alzheimers
What can overproduction of Acetylcholine be associated with?
Seizures
What does Nicotine bind to?
One type of ACh receptor
What is Norepinephrine (NE) associated with?
The fight or flight response. Also associated with learning, memory, wakefulness, eating
What are Deficiencies associated with?
Depression, excesses with stress and panic disorders
What does Dopamine (DA) play a role in?
Plays a role in reward, motivation, feelings of pleasure, and voluntary motor control
What is diminished DA associated with?
Parkinson’s disease
What is Serotonin (5-HT) associated with?
Mood, appetite, sleep, arousal, memory, learning
What are imbalances in Serotonin (5-HT) associated with?
Imbalances associated with depression, anxiety, sleeping and eating disorders
what are Endorphins?
Opiate like-substances naturally produced by the body and released during..
What are Endorphins involved in?
Pain reduction(analgesic effect) by inhibiting the transmission of pain impulses
What are Endorphins triggered by?
Various activities (painful experiences, physical. exertion, possibly during laughter, etc.)
What is an undersupply of endorphins associated with?
Pain hypersensitivity
What do Agonists do?
Increase the activity of a neurotransmitter by increasing productions, release and inhibiting uptake
What do Antagonists do?
Decrease the activity of neurotransmitters by blocking receptor sites so they cannot bind
What does the Central Nervous System consist of?
The brain and Spinal cord
What does the Peripheral Nervous system consist of?
Neurons connecting the CNS with muscles, glands and sensory receptors
What are the two subcategories of the PNS?
Somatic Nervous system
Autonomic nervous system
What is the Somatic Nervous system related to?
Voluntary behaviours
What is the Autonomic nervous system related to?
Involuntary behaviours
How much does the brain weigh?
2% of total body weights yet uses 20% of oxygen
How do most nerves enter/leave the CNS?
Through the spinal cord
What are Spinal Reflexes?
Simple stimulus response behaviours that results in motor output without any communication from the brain
