1)Based on laboratory observations (direct or indirect) draw following neurons or structures, provide spatial scale to each drawing:
1.1) Cortical pyramidal neuron
Purkinje neuron from cerebellum
6 layers of neocortex with different neuronal types
2)In a thought experiment, let’s imagine neuronal tissue enlarged 10,000 times in each direction. This way the objects of our study – neurons and neuronal networks – will reach dimensions of everyday objects we have experience with, and we will be able to visualize and understand their proportions and complexity better.
Make the following calculations:
actual dimension enlarged dimensions
neuronal cell body 10-20 micrometers in diameter ___________________
compare to everyday objects: ___________________
axon diameter ~1 micrometer ____________________
length of an axon millimeters, (up to 1 meter) ____________________
How far would the enlarged axon reach from your current location? ____________________
total dendritic length ~15 mm ____________________
size of a synapse 1-2 micrometers ____________________
synaptic gap 20-40 nanometers ____________________
density of synapses on dendrite ~1 per micrometer ____________________
density of neurons 100 000 per mm3 ____________________
How many enlarged neurons would fit into a telephone booth? ____________________
area of human neocortex 40 cm x 40 cm ____________________
How large area of your hometown would be covered by enlarged cortex? ____________________
3) Essay question: Describe four staining methods, show how they complement each other and think what types of questions each method could answer. (Provide one-page answer.)