The Effect of Magnetic Fields on C

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Nov 16, 2013 (3 years and 9 months ago)

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1








The Effect of Magnetic Fields on
C. elegans

Reproduction

and

Sensitivity to Touch

Stimulus

Roshelle Belfer

IB Candidate Number:
002904
-
078

Biotechnology High School

May 2012 Exam Session

Diploma Program
me
, Group 4

Supervisor: Julie Nowicki

Word Count:
3,672








2

Abstract

This experiment investigate
d

whether the presence of a ma
gnetic field would result

in an effect on
C. elegans
, specifically with regard to its rate of reproduction

(
whether the amount of worms
increased or decreased
)

and sensitivity to touch

(whether the worm
s
respond
ed

to a stimulus)
.

Neodymium disc magnets were used to observe the presence of a magnetic field, and the control
group was the group of
C. elegans

that was not exposed to magnets
.

Several studies found th
at
magnets typically cause negative results in
C. elegans
,
with specific regard to reproduction and
development. T
herefore, t
his experiment was conducted in order to observe whether
those studies
were accurate.

The hypothesis stated that the r
eproduction r
ate would decrease and that

C. elegans

would
react

differently than

the typical response to a stimulus and
not
jerk backward as

a response
to touch
. The data supported both

aspects of the hypothesis: the

reproduction rate did decrease and

sensitivity

to to
uch was generally atypical

when exposed to a magnetic field. These results
support
ed
the idea
that the presence of a magnet does tend to evoke a negative reaction in
C.
elegans
, most likely because the magnetic field disrupts normal
bodily
functions.




Word Count: 193















3

Table of Contents

Title Page
……………………………………………………………………………………Page 1

Abstract……………………………………………………………………………………..
.
Page 2

Contents Page..
.……………………………………………………………………………..
.
Page 3

Introduction...…………………
…………………………………………………………
...
Page
4
-
6

Materials……...……………
……………………………………………………………….
..
Page 6

Methods...…………………
……………………………………………………………...
.
Page
6
-
9

Results…………………………………………………………………………………...
.
Page 9
-
14

Analysis and Evaluation………………………………………………………………
..
Page 14
-
17

Conclusion………………………………………………………………
……………...
.....
Page
17

Literature Cited…………………………………………………………………………….
Page 18

Appendix………………………………………………………………………………..
Page 19
-
25













4

Introduction
:

The phenomenon of magnetism is controlled by magnetic fields. A magnetic field is formed by an
electric
current, and that field, in turn, spreads magnetic forces to other particles in the field (Nave,
2003). In relation to everyday magnets, a magnetic field refers to the force surrounding a magnet
that attracts or repels certain objects. Magnetic fields are
most often measured using the Tesla
(abbreviated as “T”) unit.


In this experiment, the effect of

a magnetic field was tested on the nematode
Caenorhabditis
elegans

to observe any possible changes in reproduction

and response to
a stimulus
. N
eodymium
disc magnets were used to
apply

the presence of a magnetic field, and the control group was the
group of
C. elegans

that were
not exposed to magnetic fields.


Neodymium

disc magnets were used on the
C. elegans

in this experiment
due to their stron
g
magnetic fields. These magnets are created from an alloy of neodymium, iron, and boron to form a
crystalline structure

(Earth Magnet Co., 2010)
. This material is currently the strongest known type
of permanent magnet, with a residual magnetic field stren
gth of about 1 Tesla
.


C. elegans

was tested in this experiment due to its attractiveness as a model organism.
There are
several

characteristics

which

make
C. elegans

a

model

organism for the study of reproduction and
touch response.

C. elegans

is
simple

to sustain in the laboratory; it can be placed on a growth
medium in Petri dishes and left to develop

without many
provisions
.
C. elegans

is a
eukaryote
,
meaning

that its
molecular structures, such as membrane
-
bound organelles,
are similar to those in

mo
re advanced

organisms.
C. elegans

is a multi
-
cellular
creature

as well
,
meaning

that it
under
goes a
n

intricate

growth process
.

Consequently
,
scientific

data

acquire
d

from

observing

C.
elegans

may be
germane

to more
advanced

organisms, such as humans, which

are
rather

more
5

obstinate to

experimentation

(
Yakin, 2009
)
.

This model organism

address
es

fundamental questions
in behavioral biology
, such as whether reproduction rates and response to stimulus are affected by
magnetic fields
.


In general, most biological organisms
respond

to Earth’s magnetic fields continuously; although,
these

responses
are not very
significant
. If the
normal state of a biological

organism
is perturbed by

an intense

magnetic field, however, the organ
ism will no
tably
respond to this

stimulus
.
Some
researchers have found that living tissues are greatly affected by minute variations in magnetic
field strength. Higher strength values may impact metabolic development, thus jeopardizing the
tissues (Biomag, 2006).


On
e study (
Bessho
,
Yamada
,
Kunitani
,
Nakamura
,
Hashiguchi
,
Tanimot
o
,
Harada
,
Yamamoto

&
Hosono
, 1995) found that at high magnetic fields, like alternating
-
current magnetic stimuli as high
as 1.7T,
C. elegans
reproduction, post
-
embryonic development, and locomotion were all
negatively affected. Reproduction and post
-
embryonic development were both found to have been
slightly inhibited, and locomotion became slightly deranged. A second study found that when
C.
e
legans

were exposed to electromagnetic fields, their stress
-
response protein production drastically
increased (Cranfield, Dawe, Karloukovski, Dunin
-
Borkowski, de Pomerai, & Dobson, 2004).


According to all of the gathered information
, the
C. elegans

were e
xpected to develop a negative
reaction when exposed to the magnet. It was hypothesized that the reproduction rate would
decrease, due to the disruptive effect that magnetic fields seem to have on
C. elegans
. Regarding
response to
a stimulus
, it was predict
ed that
C. elegans

would display
the

normal movement,
meaning they would
jerk

backward when tou
ched in the head by an eyelash, in an attempt to move
away from the assailant

(Hart, 2006)
.

6

Materials
:

The material
s used in this experiment were: ethanol, glove
s, goggles, NGM agar, water bath, Petri
dishes, sharpie marker, hot gloves, Parafilm, culture tube, 5
-
mL serological pipet, 5
-
mL pipet
pump, LB broth, sterile inoculating loop, OP50 bacterial stock culture, bacterial waste beaker,
incubator turned to 37 de
grees Celsius, micropipet, micropipet tips, L
-
spreader, flame stick,
scalpel,
C. elegans

stock culture, disposable pipet, clay, eyebrow hair, neodymium disc magnets,
timer, and dissecting microscope.


Methods
:

For this experiment, the independent variable
was the presence of a magnetic field. The dependent
variable was the rate of reproduction, or the population size, and the response to a touch stimulus.
Controlled variables included the same growth media (NGM agar),
the amount of trials in each
group,
the

incubation temperature
(37 degrees Celsius),
the strength of the magnet (1 Tesla),
the
size of each sample of worms in the Petri dish (1 inch)
,
and the chance of contamination was
diminished by
applying

a sterile technique.


The common technique for
developing a

C. elegans

culture
was used

(
Stiernagle, 2006)
.
First, t
he
working area was sterilized with ethanol. In order to pour NGM agar plates for
C. elegans

culture,
the previously prepared bottle of NGM agar was obtained and heated up in a hot water
bath.
Twenty Petri dishes were labeled with initials, date, “NGM agar”, and group number. There should
be four groups of five dishes: two groups were used for observing change in reproduction and two
groups were used to observe change in
response to
a stim
ulus
. The first two groups were used for
observation of reproduction: Group 1 was used for the controls (witho
ut any magnetic exposure),
and G
roup 2 was exposed to neodymium disc magnets, which have the magnetic strength of
7

approximately 1T. The last two g
roups were used for observation of
response to a stimulus
: Group
3 was the controls (without any magnetic exposure), and group 4 was exposed to the 1T
neodymium disc magnets. One extra dish was labeled as a
C. elegans
stock plate.

Once the agar in
the wate
r bath was sufficiently heated, it was poured into the twenty
-
one labeled Petri dishes. The
plates were allowed time to cool, after which they were wrapped in Parafilm and stored away. In
order to prepare bacterial food for
C. elegans
, a culture tube was o
btained and labeled with initials,
date, and “OP50”. Using a five
-
mL serological pipet and its corresponding pipet pump, five mL of
LB broth was transferred into the labeled culture tube. Using a sterile inoculating loop, a bit of E.
coli bacteria was scra
ped from the OP50 stock culture and placed into the culture tube. The culture
tube


now containing the broth and
E.coli



was placed into
an

incubator

set at 37 degrees
Celsius
.


In order to prepare the NGM plates for
C. elegans
culture, a micropipet was
used to transfer one
hundred microliters of OP50
E.coli

broth to each of the prepared NGM plates. An L
-
spreader was
used to spread the bacterial broth out on each of the 20 plates. The plates were wrapped in Parafilm
and stored away.


In order to chunk
C.
elegans
, a scalpel was sterilized with a flame stick. Using the sterilized
scalpel, a square
-
shaped chunk of
C. elegans

stock culture was cut out from a Petri dish. (This
stock culture was created by chunking, in order to have a supply of worms for experim
entation.)
Three chunks were placed into each NGM plate. After chunking, all of the plates were wrapped in
Parafilm and inverted. The plates were stored away, and were allowed a few days’ time for the
worms to replicate sufficiently.


8

To observe how differ
ent magnetic strengths affect reproduction, the ten Petri dishes for Group 1
and Group 2 were obtained. For Group 1, no magnetic field was applied; they were simply left
unaffected. For Group 2, however, the five neodymium disc magnets and a timer were gat
hered.
One neodymium disc magnet was placed next to each dish in Group 2 for fifteen minutes.
(In the
“Biological Responses in
C
. elegans

to High Magnetic F
ields
” article, the time for exposure to a
magnetic field was much longer, but due to time constraints during the experiment, fifteen minutes
was the minimum amount of time that could be allowed.)
After fifteen minutes was complete, the
plates were wrapped in P
arafilm and stored away for next class. A few days were required to pass
before observing change in reproduction; the amount of offspring produced can’t be recorded
immediately after exposure because there would be no change. After those few days had passe
d,
the Group 1 and Group 2 plates were gathered again, in addition to a dissecting microscope. The
plates were observed under the microscope and the amount of worms present in one 1
-
inch sample
of each plate was counted. A sample was used in order to avoid

counting the thousands of worms
on the entire plate. Reproduction observations were recorded for the next several classes.


To observe how different magnet
ic strengths affect response to a
touch
stimulus,

a worm poking
device was required

to be made
. In o
rder to create this device,

a disposable pipet was obtained. A
small piece of clay was placed at the narrow end of the pipet, and an eyebrow hair was attached to
the clay. This small hair would be used to poke the worms and examine their reactions.


T
he te
n Petri dishes for Group 3 and Group 4 were obtained. For Group 3, no magnetic field was
applied. For Group 4, however, the five neodymium disc magnets and a timer were gathered. One
neodymium disc magnet was placed next to each dish in Group 4 for fifteen

minutes. Due to the
fact that sensitivity to touch can be observed immediately after exposure, like locomotion
behavior, a dissecting microscope was obtained as soon as the fifteen minutes were complete. The
9

plates were placed under the microscope and one

1
-
inch sample of each plate was observed. As
with reproduction, a sample was used in order to avoid counting the thousands of worms on the
entire plate. In each sample, five worms were poked on the head with the previously made worm
poke and were observed

to see if they demonstrated a pattern other than normal behavior. Normal
behavior is
categorized as

the
behavior in which the worm

jerks its head away from the poke
, to
move away from the
stimulus
. The worms were observed to see if their behavior deviated

from
this. These touch response observations were recorded for the next several classes.


Results
:

This experiment includes six days of data for each
of the two
parameter
s that were

measured: the
rate of reproduction and the response to a touch stimulus.


The following data table depicts the average rate of reproduction
with

exposure to magnetic fields
over
a six
-
day time period
:

(
Note: T
he average of each day was

taken
. Each of t
he complete data tables may be found in the
appendix
, along with a sample
calculation of the averages
.
)


Table 1: Average Rate of Reproduction in
C. elegans

exposed to magnetic fields


Day 1

Day 2

Day 3

Day 4

Day 5

Day 6


Mean
Number of
Worms


216


198


142


118


90


69


± Standard
Deviation


24.9


34


32.9


28.5


27.2


20.5


This data table
demonstrates

a steady

decrease

in the rate of reproduction of
C
. elegans
.
In the
beginning, the amount of worms was found to be 216.
The effect began slowly and there was not a
10

drastically significant change in p
opulation size for the
first two

days.
However, as magnetic fields
were applied to the
C
. elegans
, the reproduction became affected and the number of worms on
each plate began to diminish

considerably.


The following data table depicts the average rate of reproduction
without

ex
posure to magnetic
fields over a six
-
day time period:


Table 2
: Average Rate of Reproduction in
C. elegans

not
exposed to magnetic fields


Day 1

Day 2

Day 3

Day 4

Day 5

Day 6


Mean
Number of
Worms


205


196


147


113


101


95


± Standard
Deviation


24.9


34


32.9


28.5


27.2


20.5


This data table
is similar to the previous table because it likewise demonstrates

a steady

decrease
in the rate of reproduction of
C
. elegans
. However, there are a slightly larger number of worms in
this table. This is most likely due to the fact that
C
. elegans

reproduction rate, and therefore
population size, can indeed be affected by the presence of a magnetic field. So without the
presence
of a magnetic field,
C
. elegans

population size is larger than the other group exposed to a
magnetic field
.
When

magnetic fields were applied to the
C
. elegans
, the reproduction became
affected and the number of worms on each plate began to diminish consid
erably

more so than in
this group
.

Thus, the rate of reproduction
will always decrease over time
, but the presence of a
magnetic field increases that rate even further.


T
he following line graph
s

summarize

the data in the
two data
table
s

and demonstrat
e

th
e
decrease
in the
average rate of reproduction over the
six
-
day time period
:

11

The Effect of Exposure to Magnets on C. elegans
Reproduction Rate
0
50
100
150
200
250
300
1
2
3
4
5
6
Day
Average amount of worms
in 1-cm sample
Exposure to
magnets

The Effect of No Exposure to Magnets on C.
elegans Reproduction Rate
0
50
100
150
200
250
1
2
3
4
5
6
Day
Average amount of worms in
1-cm sample
No exposure to
magnets


In the
s
e

graph
s
,
the trials that weren’t exposed to magnets begin
with

the smallest amount of
worms. However, at
around
D
ay 3, the worms that were exposed to magnets turn
ed

around and
demonstrated a drastically de
creased reproduction rate compared to the worms without magnetic
exposure. The result
s after Day 2
support

the

hypothesis.


Table 3:
T
-
test data for control
vs. treated reproduction groups


Day 1

Day 2

Day 3

Day 4

D
ay 5

Day 6

P value

0.199

0.428

0.415

0.372

0.17
7

0.00
3

12

In order for there to be a significant difference in the data, the P value needs to be below 0.05.
Almost none of these are found to show significant differences between the worms under normal
conditions and the worms exposed to magnets; only one out of six shows a significant difference.
Therefore, the treated groups are not extensively affected by exposure to magnetic fields.


Regarding response to touch, t
he following data table depicts the average
response to

touch
stimulus
with

exposure to magnetic fields over
a three
-
day time period:

(Note: Raw data can be seen in appendix.)


Table 4: Average
C. elegans

response to touch stimulus when

exposed to magnetic

fields


Day 1

Day 2

Day 3


Mean
% Normal
Responses

21

/ 25

=
84
%

21

/ 25

=
84
%

22

/ 25

=
88
%


± Standard
Deviation

0.57

0.53

0.61


In this data table, the percentages of normal responses to a touch stimulus were found in be in the
80
th

percentile range. Most responses were normal, but several were abnormal.
This abnormal
category included worms that didn’t respond at all and worms that moved
toward

the touch
stimulus. These types of abnormal responses were most likely

caused by the presence of magnets.


The following data table depicts the average
response to touch stimulus

without

exposure to
magnetic fields over
a three
-
day time period:


Table 5: Average
C. elegans

response to touch stimulus when not exposed to magne
tic fields


Day 1

Day 2

Day 3


% Normal
Responses

23 / 25

=
92%

24 / 25

=
96%

24 / 25

=
96%


± Standard
Deviation

0.
4
8

0.54

0.5
2


13

This data table
is similar to the previous table because it likewise demonstrates

that most of the

C
.
elegans

responses to a touch stimulus were normal
.

However, this table shows slightly higher
values


in the 90
th

percentile range, rather than the 80
th
. Therefore, without
exposure to
a
magnetic

field
,
C
. elegans

tend to have more normal responses to touch stimu
li.


The following bar graphs summarize the data in the two data tables and demonstrate the
percentage of normal responses to touch stimulus
over the three
-
day time period
:



1
4

In these graphs, the trials that weren’t exposed to magnets
demonstrated a high
er percentage of
normal responses to touch stimulus. Although the difference in percentage is not very drastic since
the percentage only fluctuates by approximately ten percent,
C
. elegans

is still shown to have less
normal responses when exposed to a magn
etic field
. The
se

result
s
support

the

hypothesis.


Analysis and Evaluation:

O
n Day 1,
r
eproduction data demonstrated an initial amount of worms that wa
s at approximately
two
-
hundred.

Touch response

data showed

that the
C
. elegans

exposed to magnetic fields showed
a higher amount of abnormal responses
. Almost all of the worms not exposed to magnets
demonstrated normal behavior
, a
nd four of the worms exposed to magnets demonstrated abnormal
behavior.


Day 2 was the first day in whic
h magnetic exposure data was recorded

for reproduction
.
The
amount of worms stayed at

around 200 in each trial
;
there was

not much variation

from the
numbers recorded on Day 1
.
M
ost of the time, the amount of worms in each trial decreased b
y
approximately
10 or 20

worms.

Touch response data continued the same general trend: the
C
.
elegans

exposed to magnets demonstrated more abnormal responses than the worms under normal
conditions.

Almost every
worm not exposed to magnets

demonstrated normal behavior.


O
n Day 3, the amount of worms in each trial began to drastically decrease, by about forty or fifty
worms, finally demonstrating the expected decline in reproduction rate.
Regarding
response to

touch stimulus, the pattern remained unchanged: the worms that d
id not receive magnetic exposure
demonstrated a greater number of normal responses than the worms exposed to magnets.

Every
worm

that was not exposed to magnets
, with the exception of one, demonstrated normal behavior.


15

On Day 4,
the amount of worms
was st
ill drastically decreasing

by about forty or fifty worms.
This
day seems to be the fastest time of
C. elegans

population decrease.
An error occurred in which the
worms in Groups 3 and 4 seemed to have disappeared. Therefore, the touch response data was
imp
eded. However, enough data was gained to understand the general trend: the worms exposed to
magnets were affected more negatively than the normal worms and thus responded more
abnormally.


On Day 5, the amount of worms continued to decline at a rate of app
r
oximately forty to fifty
worms. This r
ate of steady decline shows the negative impact of magnetic exposure upon
C.
elegans
.


On Day 6,
the rate of reproduction continued to decrease gradually; however, it decreased at a
slightly slower rate of twenty to t
hirty worms instead of a rate of forty to fifty.



The hypothesis stated

that the reproduction rate would
decrease and that

C. elegans

would
not
jerk
backward
,

as a
n

ab
normal response to a touch stimulus
.

The data supported al
l aspects of the
hypothesis: the reproduction rate
did decrease

and

sensitivity to touch was generally abnormal
when exposed to a magnetic fiel
d
.

However, this data did not show very drastic changes.
The
reproduction data
showed that worms under normal con
ditions did indeed have higher rates of
reproduction. Yet the worms exposed to magnets only showed a slightly higher population size;
oftentimes, the difference in size was merely ten or fifteen worms, which is not very much at all.

The touch response data

demonstrated that worms under normal conditions were only slightly
more likely to have normal responses to touch stimuli; the percent
difference

between the two
groups was merely ten percent.
Therefore, it can be concluded
that
although magnetic exposure
does cause negative responses in
C. elegans
,
these responses are often very miniscule
.
T
he cause
16

of the
s
e

negative responses
was
most likely
due

to the disruptive effect that magnetic fields seem
to have on
C. elegans
.

The Japanese study mentioned previous
ly produced similar results: at high
magnetic fields,
C. elegans
reproduction was slightly in
hibited and

its movements

became slightly
deranged (
Bessho
,
Yamada
,
Kunitani
,
Nakamura
,
Hashiguchi
,
Tanimoto
,
Harada
,
Yamamoto

&
Hosono
, 1995), just like the results of this experiment.


However, t
here were several
errors in

this experiment. First of all, it wasn’t possible to perfor
m a t
-
test for the touch response data. The values were too small, and it would not have been possible to
determine whether any of the values showed significance or not.

Also, t
here were several
exceptions in each day

regarding the rate of reproduction
, in

which the amount of worms
increased, rather than decreased. This unexpected increase could have been caused by the
inaccurate exposure of magnets; for example, the timing may have been off

and the
C. elegans

might not have been exposed to the magnet for a long enough time to have any effect

on its
functions
.

This could be fixed by keeping a more careful watch at the timing of magnetic exposure.


Furthermore,
animals can
sometimes
give a partial response to to
uch stimulus.
Even
touch
-
insensitive animals
may
sometimes respond to the first touch

(Hart, 2006
)
. To provide a more
quantitative measure of
sensitivity to touch
, one
could

count the re
sponse
s to multiple touches, or

touch
the worms
with defined stimuli,
such as flexible fiber “hairs
”,

called von Frey hairs. These
“hairs” are more firm and would allow for an improved touch response.


The continuation of this experiment might prove
to be valuable
. Now that it is
supposed

that
magnetic fields negatively affe
ct
C. elegans
, it may be valuable to
perform more trials and
test
di
fferent strengths of magnets to

observe which strength
C. elegans

may be able to tolerate
, instead
of simply comparing the effect of the presence of a magnet
.

The magnets used in this expe
riment
17

were roughly around the strength of one Tesla; it could be possible to obtain magnets in strengths
such as 0.5 Tesla, 1 Tesla, 1.5 Tesla, etc. and record the effects that those various magnets cause in
C. elegans
.

Other biological organisms, possibl
y even humans, could be tested as well in order to
compare responses throughout different species of life.


Conclusion
:

The exposure of magnetism on
C. elegans

proved to have a slightly successful effect on the rate of
reproduction.

The population size decreased

at a faster rate than the control

over the course of the
six days,
supporting the hypothesis
.
Sensitivity
to touch
also produced positive data: t
he worms
exposed to magnets demonstrated more abnormal reactions that the worms
under normal
conditions
.
However, these results did not display very significant changes.
The reproduction data
showed that worms under normal conditions did indeed have higher rates of reproduction, but the
worms exposed to magnets only showed a slightly
higher population size; the difference in size
was extremely small and insignificant. The touch response data followed a similar pattern. Worms
under normal conditions were found to have only slightly more normal responses to touch stimuli;
the percent dif
ference between the two groups was merely ten percent. Therefore, it can be
concluded
that
although magnetic exposure does cause negative responses in
C. elegans
, these
responses are often very miniscule.







18

Literature Cited

Bessho, K, Yamada, S, Kunita
ni, T, Nakumara, T, Hashiguchi, T, Tanimoto, Y, Harada,

S, Yamamoto, H, & Hosono, R (1995). Biological responses in c elegans to high magnetic
fields.
Cellular and Molecular Life Sciences
,
51
(3), Retrieved from
http://www.springerlink.com/content/x07100k5
22548410/

Biomag (2006).
Harmful magnetic field
. Retrieved from

http://www.magnetotherapy.eu/magnetotherapy
-
magnetotherapy/magnetotherapy
-

harmful
-
strong
-
magnetic
-
field.php

Cranfield, C, Dawe, A, Karloukovski, V, Dunin
-
Borkowski, R, De Pomerai, D, &

Dobson, J

(2004). Biogenic magnetite in the nematode caenorhabditis elegans.
Proceedings:

Biological Sciences
,
271
(6), Retrieved from http://www.jstor.org/stable/4143030

Earth Magnet Co. (2010).
Neodymium magnets
. Retrieved from

http://www.permanentmagnet.com/neodymium_magnet.html

Hart, A. (2006, July).
C. elegans behavior
. Retrieved from

http://www.wormbook.org/chapters/www_behavior/behavior.html

Nave, R. (2003).
Magnetic fields
. Retrieved from http://hyperphysics.phy
-

astr.gsu.
edu/hbase/magnetic/magfie.html

Stiernagle, T.
(February 11, 2006)
.
Maintenance of

C. elegans
,
WormBook
, ed. The
C. elegans


Research Community, WormBook, doi/10.1895/wormbook.1.101.1,
http://www.wormbook.org
.

Yakin, R. (2009).
Introduction to c. elegans
. R
etrieved from

http://avery.rutgers.edu/WSSP/StudentScholars/project/introduction/worms.html



19

Appendix

Reproduction
Data Collection
:

Day 1


Group Number


Trial Number

Amount of Worms in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

241

2

217

3

239

4

194

5

187


2

(No Magnetic Exposure)

1

196

2

204

3

242

4

217

5

165

In this table, the amount of worms recorded is typically around 200 in each trial. This is the initial
amount of worms, to which magnets have not yet been applied.



Reproduction
Data Collection
:

Day 2


Group Number


Trial Number

Amount of Worms in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

188

2

209

3

252

4

165

5

178


2

(No Magnetic Exposure)

1

181

2

202

3

237

4

213

5

146

This is the first day in which magnetic
exposure data was recorded. In this table, the amount of
worms is typically around 200 in each trial. For most of the time, the amount of worms in each
trial decreased by approximately 20 or 30 worms. The only exception was Trial 3 in Group 1,
which increa
sed by 13 worms. This could have been caused by an improper exposure of magnets
(the timing may have been off).


20

Reproduction
Data Collection
:

Day 3


Group Number


Trial Number

Amount of Worms in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

104

2

138

3

192

4

126

5

152


2

(No Magnetic Exposure)

1

116

2

183

3

197

4

149

5

88

In this table, the amount of worms in each trial varies drastically. The range is approximately 80 to
200 worms, which is quite a stretch. The rate of reproduction, however, seemed to maintain a rate
of constant decline. For most of the time, the amount of

worms in each trial decreased by
approximately 40 or 50 worms.



Reproduction
Data Collection
:

Day 4


Group Number


Trial Number

Amount of Worms in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

152

2

87

3

143

4

96

5

114


2

(No Magnetic Exposure)

1

108

2

127

3

136

4

118

5

74

In this table, the amount of worms in each trial again varies drastically. The range is approximately
70 to 150 worms, which is still quite a stretch. The rate of reproduction
consistently decreased
.
Generally
, the amount of worms in each trial decreased by approximately 40 or 50 worms. The
only exception was Trial
1 in Group 1, which increased
. This could have been caused by an
improper exposure of magnets (the timing may have been off).

21

Reproduction
Data Coll
ection
:

Day 5


Group Number


Trial Number

Amount of Worms in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

102

2

83

3

126

4

85

5

52


2

(No Magnetic Exposure)

1

90

2

104

3

113

4

127

5

69

In this table, the amount of worms in each trial again
varies drastically. The range is only about 50
worms to 130 worms this time, which is not as great a difference as the previous two days. The
rate of reproduction is gradually declining. The amount of worms in each trial decreased by
typically 40 or 50 wor
ms. The only exception was Trial 4 in Group 2, which increased by simply 9
worms. This could have been caused by an improper exposure of magnets (the timing may have
been off).


Reproduction
Data Collection
:

Day 6


Group Number


Trial Number

Amount of Worm
s in 1
-
cm
sample



1

(1T Magnetic Exposure)

1

66

2

53

3

85

4

94

5

46


2

(No Magnetic Exposure)

1

87

2

98

3

105

4

114

5

69

In this table, the amount of worms in each trial again varies drastically. The range is only about 50
worms to 130
worms this time, which is not as great a difference as the previous two days. The
rate of reproduction is gradually declining. The amount of worms in each trial decreased by
typically 40 or 50 worms. The only exceptions were: Trial 4 in Group 1, which incr
eased by only 9
worms, and Trial 5 in Group 2, which increased by 46 worms. These exceptions may have been
caused by an improper exposure of magnets (the timing may have been off).

22

Touch

Response Data Collection: Day
1


Group Number

Trial Number

Worm

Is to
uch response normal or abnormal?











3

(no magnetic exposure)



1

1

Normal

2

Normal

3

Normal

4

Abnormal


no movement/response

5

Normal



2

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



3

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



4

1

Normal

2

Normal

3

Abnormal


no movement/response

4

Normal

5

Normal



5

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal












4

(1T magnetic exposure)



1

1

Normal

2

Abnormal


no
movement/response

3

Normal

4

Normal

5

Normal



2

1

Normal

2

Normal

3

Abnormal


no movement/response

4

Normal

5

Normal



3

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



4

1

Abnormal


no movement/response

2

Normal

3

Normal

4

Normal

5

Abnormal


no movement/response



5

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal


A
lmost all of the worms not exposed to magnets demonstrated normal behavior, with the exception
of two (out of twenty
-
five). And
four of the worms exposed to magnets demonstrated abnormal
behavior. This is twice the amo
unt of the worms not exposed to magnets.

23

Touch

Response Data Collection: Day
2


Group Number

Trial Number

Worm

Is touch response normal or abnormal?











3

(no
magnetic exposure)



1

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



2

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



3

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



4

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



5

1

Normal

2

Abnormal


no movement/response

3

Normal

4

Normal

5

Normal












4

(1T magnetic exposure)



1

1

Normal

2

Normal

3

Abnormal


no movement/response

4

Normal

5

Normal



2

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



3

1

Normal

2

Abnormal


no movement/response

3

Normal

4

Normal

5

Normal



4

1

Normal

2

Normal

3

Abnormal


no movement/response

4

Normal

5

Normal



5

1

Normal

2

Normal

3

Abnormal


no
movement/response

4

Normal

5

Normal


In this table, every single worm that was not exposed to magnets, except one, demonstrated normal
behavior. And four of the worms exposed to magnets demonstrated abnormal behavior.

24

Touch

Response Data Collection: Day
3


Group Number

Trial Number

Worm

Is touch response normal or abnormal?











3

(no magnetic exposure)



1

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



2

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



3

1

Normal

2

Abnormal


no movement/response

3

Normal

4

Normal

5

Normal



4

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



5

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal












4

(1T magnetic
exposure)



1

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal



2

1

Normal

2

Abnormal


no movement/response

3

Normal

4

Normal

5

Normal



3

1

Normal

2

Normal

3

Normal

4

Normal

5

Abnormal


no movement/response



4

1

Normal

2

Normal

3

Abnormal


no movement/response

4

Normal

5

Normal



5

1

Normal

2

Normal

3

Normal

4

Normal

5

Normal


In this table, every single worm not exposed to magnets, except for one, demonstrated normal
behavior. And three of the worms exposed to magnets demonstrated abnormal behavior.

25

Average:

Sample Calculation


Average for Day 3 of Reproduction Data

Trial 1:
104 worms

Trial 2: 138 worms

Trial 3: 192 worms

Trial 4: 126 worms

Trial 5: 152 worms

104 + 138 + 192 + 126 + 152 = 712

712 / 5 = 142 worms


Standard Deviation: Sample Calculation

SD = sqrt {sum(x


mean)² / (n


1) }

For the standard deviation of 104, 138
, 192, 126, and 152 (Data for Day 3 of Reproduction):

104 + 138 + 192 + 126 + 152 = 712

712 / 5 = 142 worms

x

104

138

192

126

152

(x
-
x)²

1444

16

2500

256

100


Sigma = 1444 + 16 + 2500 + 256 + 100 = 4316

n


1 = 5


1 = 4

4316 / 4 = 1079

Square root of

1079 = 32.85


26

T
-
test
:

Sample Calculation


Once the t
-
value is computed, a table of significance
must be referenced
to

in order to

test
the
statistical
difference between the groups.
The risk level

should be .05; meaning

that five times out
of a hundred
one

would find a statistically significant difference between the
averages
, and the
degrees of freedom should be the amount of groups, minus one
.


Table

of Critical Values for T


df

0.10 0.05 0.025 0.01 0.005 0.001




1.

3.078 6.314 12.706 31.821 63.66

318.313


2. 1.886 2.920 4.303 6.965 9.925

22.327


3. 1.638 2.353 3.182 4.541 5.841

10.215


4. 1.533 2.132 2.776 3.747 4.604 7.173


5. 1.476 2.015 2.571 3
.365 4.032 5.893


6. 1.440 1.943 2.447 3.143 3.707 5.208


7. 1.415 1.895 2.365 2.998 3.499 4.782


8. 1.397 1.860 2.306 2.896 3.355 4.499


9. 1.383 1.833 2.262 2.821 3.250 4.296


10.


1.372 1.812 2.228 2.764 3.169 4.143


20.

1.325 1.725 2.086 2.528 2.845 3.552


30.

1.310 1.697 2.042 2.457 2.750 3.385


40.

1.303 1.684 2.021 2.423 2.704 3.307


50.


1.299 1.676 2.009 2.403


2.678 3.261


60.

1.296 1.671 2.000 2.390 2.660 3.232


70.

1.294 1.667 1.994 2.381 2.648 3.211


80.
1.292 1.664 1.990 2.374 2.639 3.195


90.

1.291 1.662 1.987 2.368 2.632 3.183

100.


1.290

1.660 1.984 2.364 2.626 3.174




1.282 1.645 1.960 2.326 2.576 3.090