Lecture 10 Flashcards
Describe the main 3 features of a neuron and their associated function AND synapse
Most neurons have a cell body, an axon, and dendrites.
The cell body contains the nucleus and cytoplasm. The axon extends from the cell body and often gives rise to many smaller branches before ending at nerve terminals.
Dendrites extend from the neuron cell body and receive messages from other neurons.
Synapses are the contact points where one neuron communicates with another.
The dendrites are covered with synapses formed by the ends of axons from other neurons.
Define neuron
Neurons are cells within the nervous system that transmit information to other nerve cells, muscle, or gland cells
Basic functional unit of
nervous system
Features:
Excitability or Conductivity
Draw and label a neuron
Lecture Slide Dendrites Cell body Axon Neural Impulse Myelin Sheath Terminal branches of axon
Pre and Post synaptic neuron
Synapse
junction point between two neurons.
typical chemical synapse between two neurons, the neuron from which the nerve impulse is generated and transmitted is called the presynaptic neuron.
The neuron to which the neurotransmitters (chemical messengers) bind is called the postsynaptic neuron.
Draw a synapse
Lecture slide: Vesicles Synaptic gap Neurotransmitters Neurotransmitter receptor presynaptic neuron. postsynaptic neuron.
Draw the diagram of action potential
Lecture slide
Describe the phases of action potential.
Hypo polarisation
initial increase of the membrane potential to the value of the threshold potential
Depolarisation
opens voltage-gated sodium channels and causes a large influx of sodium ions
Overshoot
inside of the cell becomes more and more electropositive, until the potential gets closer the electrochemical equilibrium for sodium of +61 mV.
Repolarisation
• sodium permeability suddenly decreases due to the closing of its channels.
• overshoot value of the cell potential opens voltage-gated potassium channels, which causes a large potassium efflux, decreasing the cell’s electropositivity.
Hyperpolarisation
a state in which the membrane potential is more negative than the default membrane potential
Neurotransmitters: Acetylcholine
excitatory neurotransmitter that triggers muscle contraction and stimulates the excretion of certain hormones.
Neurotransmitters: Dopamine
neurotransmitter involved in controlling movement and posture. It also modulates mood and plays a central rolein positive reinforcement and dependency.
Neurotransmitters: Gamma aminobutyric acid
inhibitory neurotransmitter that is very widely distributed in the neurons of the cortex.
Neurotransmitters: Serotonin
contributes to various functions, such as regulating body temperature, sleep, mood, appetite, and pain
Neurotransmitters: Glutamate
excitatory neurotransmitter associated with learning and memory.
Neurotransmitters: Norepinephrine
that is important for attentiveness, emotions, sleeping, dreaming, and learning.
Describe Alzheimer’s:
is a syndrome due to disease of the brain, usually of chronic or progressive nature, in which there is impairment of multiple higher cortical functions, including memory, thinking, orientation, calculation, learning capacity, language and judgement.
4 main groups of Alzheimers
Early onset
Late onset
Atypical
Unspecified
