Voluntary Actions: They are type of actions which are not forced or reflex. They are controlled actions. For example:
A Neurone
Source:
http://www.bbc.co.uk/schools/gcsebitesize/biology/humansasorganisms/4nervoussystemrev3.shtml
Sense organs or Receptors
There are many receptors in our body. They are:
The sense organs that will be tested in this experiment are the Eyes. The eyes are sense organs that respond to light and they contain specialized cells called Photoreceptors. They are light sensitive and form an image on the retina. Colored light/ image can only be pictured because of the Cones present at the Fovea. They work in the day. The Rods however can portray only black and white image and are largely used during night i.e. in absence of light. The Cones are greater in number than the Rods present in the eye. The eye senses the image being formed on the retina and then sends an impulse through the optic nerve to the C.N.S and as a result, one can see the image.
Retina
Source
http://www.bbc.co.uk/schools/gcsebitesize/biology/humansasorganisms/4nervoussystemrev5.shtml
Sense Organs and their Functions
Source
http://www.bbc.co.uk/schools/gcsebitesize/biology/humansasorganisms/4nervoussystemrev2.shtml
Hypothesis
The Males will have a faster reaction time than the Females. Also the more preferred hand will have a reaction time faster than the other hand.
Apparatus
Method
- Ask the subject to sit on the stool besides the high rise flat surface.
- Place the Stand and Clamp on the surface.
- Open the clamp such that the meter rule can easily slide pass through it.
- Keep the meter rule in such a position that the 0 cm on the rule is at the eye level of the subject.
- Place the meter rule in between the clamp.
- Place the subject’s index and middle finger of the right hand around the 0 cm mark.
- Make sure that the distance between the two fingers should be 5 cm.
- Tell the subject when you will be dropping the meter rule 5 seconds in advance.
- Ask the subject to concentrate on the falling meter rule.
- Repeat the experiment with other Male and Female subjects and their respective right and left hands.
Results
Right Hand
Left Hand
Note
Graphs
Evaluating the Graphs
Males
It can be note that all the males follow a certain pattern. The reaction time of their respective preferred hand was significantly faster than their other hand. Mustafa had the smallest reaction time whilst Sagar had the largest. On an average, Abhishek’s right hand reaction time was 12.33 cm (2 decimal places). It shows a slow reaction time. This means that the speed at which Abhishek responded to the stimuli (falling meter rule) was slow. This could have happened may because Abhishek was not concentrating on the scale as he was told to. Abhishek’s left hand average was 13.67 cm (2 decimal places). This is a small but significant difference. Mustafa on the other hand had a very fast reaction rate. His reaction time on an average turned out to be 6.67 cm (2 decimal places). However his left hand average was 8 cm. Hence it can be concluded that he did concentrate during the experiment and he had more control over his right hand than his left. Sagar’s left and right hand average readings were 16 cm and 19.33 cm (2 decimal places). It shows a very significant difference of 3.33 cm. It hence proves a part of my hypothesis that the reaction time of the preferred hand is faster than that of the not preferred one.
Females
It should be noted that only Sayali and Jahnavi had their preferred hand as the Right hand while Shloka had of the Left hand. As a result Shloka’s left hand reaction time were much quicker than the ones with the right. hence it can be asserted that all the female subjects followed the certain pattern that the reaction time of the preferred was faster than the that of the not preferred hand. This pattern was also followed by the males. My hypothesis however was proved to be right as the males had a faster reaction than that of the females. The average male reaction time including both the hands was 12.72 cm (2 decimal places) while that of the females was 12.94 cm (2 decimal places).
Average Reading = (Sum of all left and right hand readings)
No. of readings
Male = 229/18 = 12.7222 = 12.72 cm (2 decimal places)
Female = 233/18 = 12.9444 = 12.94 cm (2 decimal places)
Fair Test
- All the subjects were told when the meter rule was going to be dropped 5 seconds in advance. So it was not a reflex action.
- All subjects were asked to concentrate on the meter rule.
- The distance between the two fingers was kept at 5 cm.
Factors Affecting the Reaction Time
- Practice and Error
- Fatigue
- Sex
- Age
- Distractions
- Finger Tremors
- Left and Right hand
- Vision
Errors
- The distance between the two fingers could have marginally changed and not have been 5 cm.
- The meter rule could not have been at the exact eye level.
- The readings were rounded off to the nearest integer.
Error Analysis
Inaccuracy = Smallest reading of apparatus / 2
Total Error = Inaccuracy x No. of times used
Systematic Errors
Total Error = + 0.05 x 18 = 0.9 mm
Improvements
- The reading should be rounded of to the nearest integer.
- Subjects of different age groups should be chosen to note the trend followed.
- The subjects can be told 10 seconds in advance so that they are able to concentrate more giving accurate readings.
