Scientific Investigation - Stage 4 - 4 July 2012

Biology Lab Report

Name: Natasha Tai Qian Hui
Class: 107
Index number: 23
Date: 12 July 2012

1.   What do you want to find out? (Aim/Purpose/Research question)

The aim of the experiment is to test the mealworms’ reaction to the presence of light.

2.   What is the tentative explanation of your research question? (Hypothesis)

The mealworms will move to the area which has lower light intensity.

3.   In an investigation, there is only one variable to be changed. Which variable will you change in this investigation? (Independent Variable)

     The independent variable is the presence of light.

4.     All the other variables must be kept constant. List a few important variables that will affect the results greatly. (Controlled Variables)

      The controlled variables are:

1)   Same type of mealworms eg. same species

2)   the container is to remain at the same place throughout the entire experiment

3)   the bright and dark portion of the container must be divided into equal half

4)   the ventilation is evenly distributed on both sides of the container

5)   the food is evenly spread out over the entire container

6)   there is no extra surrounding light penetrating through the sides of the transparent plastic container

5.     What results will you measure? (Dependent Variable)

The dependent variable is the number of mealworms found in each half of the container at the end of each day for 3 days.

6.    State the assumptions that you have made

The assumptions are all the mealworms are not visually impaired and have the same sensitivity towards the presence of light.

7.     List the materials and apparatus that you will need to carry out the investigation.

(Materials and Apparatus)

Materials and Apparatus:

1. 5 mealworms

2. Plastic container

3. Black thrash bag to cover the sides of the container

4. Black paper to cover half of the lid of the container

5. Scotch tape to hold the thrash bag and black paper in place

 

8.     List the steps that you will take to carry out the investigation. (Procedure) Include drawing of setup.

Procedure:

Step 1: Wrap the sides of the container with black thrash bag. Ensure that there is no     surrounding light entering the container from the sides.

Step 2: Cover half of the lid of the container with black paper.

Step 3: Spread the food evenly at the bottom of the container.

Step 4: Place the mealworms at the center of the container

Step 5: Poke some holes on the lid and cover the lid

Step 6: Put the container in a place that receive constant light source (under a lamp).

Step 7: Observe the movement of the mealworms at the end of each day for 3 days and record the observation at the end of each day for 3 days.

Drawing of the Set-up

9.     Data collection and organization. (Results)

The data can be presented in the form of tables and/or graphs.

Results:

Number of mealworms	End of Day 1	End of Day 2	End of Day 3
Darker half of the container	3	4	6
Brighter half of the container	3	2	0

(note: there is a total of 6 mealworms in the container)

10.     Explain what your data means. (Data Analysis)

What did you observe and give reasons to your observations.

As shown in the table above, the number of mealworms at the darker half of the container at the end of day 1, day 2 and day 3 is 3, 4 and 6 out of 6 respectively. This shows that the number of mealworms at the darker half of the container increases over the period of the experiment and by the end of the experiment at the end of 3 days, all mealworms have moved to the darker half of the container.  This observation indicates that mealworms react to the presence of light by moving to the darker half of the container.   


My observations:

11.  What can you deduce from the discussion of your data analysis? (Conclusion)

State if your data support your hypothesis? If not, what would you do? In other words, how can you further improve your design? What do you think have been carried out incorrectly and affected the data collected?

Conclusion:

                                                                 

Therefore, the data collected supports my hypothesis - The mealworms will move to the area which has lower light intensity.

Length of mealworm: 3.1cm

Number of segments: 11

Colour: body is light brown, both ends of the mealworms are darker brown.

Other observable characteristics:

• The mealworm has a segmented body
• The end of the mealworm is a little pointed
• They only have six legs which are in the front part of the body.
• They have feelers