Question

Neurons have long, thin processes called axons, which are structures specialized for conducting signals throughout the organism's nervous system. Some axonal processes, such as the axons that originate in the spinal cord and terminate in the muscles of the toes, can be over 1 m in length. Small membrane‑enclosed vesicles carrying materials essential to axonal function move along microtubules of the cytoskeleton, from the cell body to the tips of the axons. Given an average vesicle velocity of 1 μm/s, how long would it take for a vesicle to move through an axon that started in the spinal cord and ended in the toes (a distance of 1 m)?

Answer 1

To calculate the time for a vesicle to travel from the spinal cord to the toes through an axon, we converted 1 meter to micrometers resulting in 1,000,000 μm. With a velocity of 1 μm/s, it would take 1,000,000 seconds, which is approximately 11.57 days.

Step-by-step explanation:

The question involves calculating the time it would take for a vesicle to move through an axon that is 1 meter in length at a velocity of 1 μm/s. To find the answer, we need to convert the distance from meters to micrometers, because the speed is given in micrometers per second. There are 1,000,000 micrometers in a meter, so the axon is 1,000,000 μm long. Now, we divide the total distance by the velocity:

Time (seconds) = Distance (μm) / Velocity (μm/s) = 1,000,000 μm / 1 μm/s = 1,000,000 seconds.

Now to convert the time to hours, we divide by the number of seconds in an hour (3600 seconds).

Time (hours) = Time (seconds) / 3600 seconds/hour = 1,000,000 seconds / 3600 seconds/hour ≈ 277.78 hours.

To convert hours to days, we divide by 24 hours/day:

Time (days) = 277.78 hours /24 hours/day ≈ 11.57 days.

Therefore, it would take approximately 11.57 days for a vesicle to travel from the spinal cord to the toes.

Answer 2

1,000,000s

Step-by-step explanation:

A micrometer (μm) is equal to 1 x 10⁻⁶ m

This means that 1 m = 1 x 10⁶ micrometers or 1,000,000 μm.

You can calculate the time it would take using the formula:

`velocity = (distance)/(time)`

So based on the formula above, you can derive the formula for time which will be:

`time=(distance)/(velocity)`

Distance = 1m or 1,000,000 μmeters

Velocity = 1μm/s

We just plug it into our formula:

`time = (distance)/(Velocity)\\\\time=(1,000,000micrometers)/(1micrometer/s)\\\\time=1,000,000s`