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Snail Lab Student

Snail Lab Student

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Page 1 of 4<br />

Name:<br />

Partner:<br />

Period:<br />

The <strong>Snail</strong> <strong>Lab</strong><br />

Observations, Interpretations, and Experimental Design<br />

You will learn how to apply the scientific method during this lab. The first step is to make<br />

observations. Then you will use the question about snail mass and speed to develop a<br />

hypothesis. The fun part is making a prediction about your hypothesis. After that, you will<br />

design an experiment that will test your hypothesis. Then you will have the opportunity to<br />

A. Observations<br />

You may not harm the animals in any way! Working with your partner, select one snail from<br />

the <strong>Snail</strong> Hotel. Place your snail (give it a name if you wish) on a wet paper towel and gently<br />

set it on your table. Record ten good observations of your snail. Make no interpretations.<br />

1.<br />

2.<br />

3.<br />

4.<br />

5.<br />

6.<br />

7.<br />

8.<br />

9.<br />

10.<br />

<strong>Snail</strong> Mass and Speed<br />

B. Question<br />

This is the question you will be addressing: Does the mass of your snail affect the speed<br />

that it crawls?<br />

1. What are the two variables in the question?

C. Hypothesis<br />

You and your partner decide on a hypothesis for the question. A hypothesis is a statement<br />

that explains an observation. H0 is your hypothesis of no difference (no effect) – There is no<br />

effect of the independent variable on the dependent variable. HA is your alternate hypothesis.<br />

H0:<br />

HA:<br />

Variables<br />

The independent variable is the factor that is the cause. The dependent variable is the effect<br />

and is influenced by the cause. A constant variable is a factor that needs to be the same for<br />

all snails tested. Fill in the following:<br />

Independent variable:<br />

Dependent variable:<br />

Constant variable 1:<br />

Constant variable 2:<br />

Constant variable 3:<br />

D. Materials & Methods<br />

Make a list of all the materials that you will need in order to conduct the experiment.<br />

Write a detailed description of how to test the effect of snail mass on speed. The level of<br />

detail must be sufficient for someone who is unfamiliar with this lab to be able to redo your<br />

experiment from your methods. Your experiment must run for at least 10 minutes.<br />

Do not proceed with your experiment until the teacher signs off on your lab write up. NO<br />

CREDIT will be given on this assignment if you do not get my signature. I will check your<br />

work and either tell you what needs to be changed or I will sign off on it.<br />

Teacher Signature<br />

Page 2 of 4

E. Results<br />

Observations and Notes<br />

Record the following: 1) observations on what you saw, 2) ideas on how to improve the<br />

Data<br />

Fill in the following table with the data collected during the experiment. Don’t forget to write in<br />

the time interval used when the snail distances are calculated (e.g., 2 minute intervals).<br />

Table 1. The distance traveled by snails for each interval<br />

<strong>Snail</strong> Mass,<br />

g<br />

<strong>Snail</strong> A<br />

<strong>Snail</strong> B<br />

<strong>Snail</strong> C<br />

Distance<br />

Travelled, cm<br />

minutes<br />

Distance<br />

Travelled, cm<br />

minutes<br />

Distance<br />

Travelled, cm<br />

minutes<br />

Page 3 of 4<br />

Distance<br />

Travelled, cm<br />

minutes<br />

Total Distance Travelled (Cumulative) = distance travelled (time 1) + distance travelled (time 2)<br />

Table 2. Total distance travelled during the experiment<br />

Time, minutes<br />

Total Distance<br />

Travelled, cm<br />

<strong>Snail</strong> A<br />

Total Distance<br />

Travelled, cm<br />

<strong>Snail</strong> B<br />

Distance<br />

Travelled, cm<br />

minutes<br />

Total Distance<br />

Travelled, cm<br />

<strong>Snail</strong> C<br />

Graph<br />

Make an XY graph (line graph) of Time and Total Distance Travelled using the data from<br />

your 3 snails. Include a title (descriptive of all variables measured and the subject organism),<br />

label the axes, indicate units (min and cm), and number the axes ticks. Include a legend<br />

that indicates which snail is graphed for each set of data points. Connect the data points for<br />

each snail with a line, starting from 0. Make sure the independent and dependent<br />

variables are on the correct axes!

F. Conclusion<br />

What is the answer to the question you set out to answer about the snails? Include the<br />