In this lab we had the opportunity to examine various types of reflexes such as the photopupillary reflex, the knee jerk reflex, and the blink reflex. A reflex is an action that takes place in response to internal signals or external signals from the environment and usually preformed without conscious thought.
To test the photopupillary reflex, one member in our group closed both of his eyes for two minutes and we positioned a flashlight close to one of his eyes. From there we had him remove one of his hands quickly in order to measure the change in size of the pupil we uncovered compared to the one that was uncovered and not exposed to a lot of light. We observed that the less light that entered the eye, the wider the pupil was; and the more light that entered the eye, the smaller it was. I believe that humans have developed this reflex in order to help them adjust to new places where they might find food or take shelter and needed to have their eyes adjust to the changing brightness of the sun throughout the day so that they could see.
One thing that I didn't know before this lab was that the blink reflex is different from the photopupillary reflex. We got to test the blink reflex by holding plastic wrap in front of a persons face in our group and throwing a cotton ball at the plastic to see if they would blink or not. Every time that we tested this, we found that people blinked when they saw the cotton ball flying towards them. I believe that this is because people try to protect their eyes as much as possible so whenever they see something coming towards their face, the usually close their eyes to prevent damage towards their eyes.
In our next experiment our group tested the knee-jerk reflex by having a group member sit and gently have another team member hit a certain spot on their knee with a reflex hammer in order to text their muscle reflex where the leg kicks out automatically. I believe that humans have evolved this reflex because of their "fight or flight" response, and when part of the body is hit, then the body's reaction is to immediately tense up and prepare itself for either defense or offense.
One of the most memorable parts of our lab was when we tested how fast our reflexes were by having a partner drop a yardstick from the air and seeing how fast the other person could catch the end of it. In the second part of this experiment we tried the same thing as above, but now you had to text with one had and grab the yardstick with the other hand (see graphs below). When comparing the two measurements, I noticed that the reaction time was almost twice as fast in the original experiment without texting. Our entire class grouped our data together, and got similar results. Based on our data, (and other data from the scientific community) if you are texting while driving, it can slow your reflexes tremendously, and people can get seriously hurt with this slower reaction time.
Our Data:
(Without texting) (While texting)
Class Data:
To test the photopupillary reflex, one member in our group closed both of his eyes for two minutes and we positioned a flashlight close to one of his eyes. From there we had him remove one of his hands quickly in order to measure the change in size of the pupil we uncovered compared to the one that was uncovered and not exposed to a lot of light. We observed that the less light that entered the eye, the wider the pupil was; and the more light that entered the eye, the smaller it was. I believe that humans have developed this reflex in order to help them adjust to new places where they might find food or take shelter and needed to have their eyes adjust to the changing brightness of the sun throughout the day so that they could see.
One thing that I didn't know before this lab was that the blink reflex is different from the photopupillary reflex. We got to test the blink reflex by holding plastic wrap in front of a persons face in our group and throwing a cotton ball at the plastic to see if they would blink or not. Every time that we tested this, we found that people blinked when they saw the cotton ball flying towards them. I believe that this is because people try to protect their eyes as much as possible so whenever they see something coming towards their face, the usually close their eyes to prevent damage towards their eyes.
In our next experiment our group tested the knee-jerk reflex by having a group member sit and gently have another team member hit a certain spot on their knee with a reflex hammer in order to text their muscle reflex where the leg kicks out automatically. I believe that humans have evolved this reflex because of their "fight or flight" response, and when part of the body is hit, then the body's reaction is to immediately tense up and prepare itself for either defense or offense.
One of the most memorable parts of our lab was when we tested how fast our reflexes were by having a partner drop a yardstick from the air and seeing how fast the other person could catch the end of it. In the second part of this experiment we tried the same thing as above, but now you had to text with one had and grab the yardstick with the other hand (see graphs below). When comparing the two measurements, I noticed that the reaction time was almost twice as fast in the original experiment without texting. Our entire class grouped our data together, and got similar results. Based on our data, (and other data from the scientific community) if you are texting while driving, it can slow your reflexes tremendously, and people can get seriously hurt with this slower reaction time.
Our Data:
(Without texting) (While texting)
Class Data:
