The Effects of Cigarette Smoke

on Yeast

Nic Jedema9th Grade

Central Catholic High School

Contain over 4000 chemicals, many of which have been shown

to be detrimental to human health.

Contain CO2 a chemical that is toxic to organisms and can be

harmful to cell growth and function.

World wide research shows that smoking is responsible for 6

million deaths annually.

It is known that cigarettes contain mutagenic and carcinogenic

substances.

Cigarettes

Smoke that is given off by the end of the smokers’ cigarette as

well as what the smoker exhales.

Detrimental to health, but it does not do as much damage as

smoking a cigarette yourself.

Is responsible for 3000 lung cancer deaths annually in non-

smokers.

Also very harmful to young children and teens as it can cause

many problems,

Secondhand Smoke

Unicellular eukaryote that has many different forms.

The most studied eukaryotic cell.

Has many characteristics that are similar to those of human cells

like nutrition and cell growth

Rely primarily on aerobic respiration to produce energy, thus if

oxygen is reduced, growth rate declines as anaerobic metabolism is

activated.

Yeast

Purpose Many people in America and all over the world smoke

cigarettes.

How much damage do these people cause to themselves and

others?

The purpose of this experiment was to determine which type of

cigarette causes the least amount of damage to smokers cells.

Yeast was used as a human cell analog

Hypotheses

Null: Cigarette

smoke will not have

a significant effect

on yeast

survivorship.

Alternative: Cigarette

smoke will reduce

yeast survivorship.

Materials Yeast culture Saccharomyces Cerevisiae

44 sterile YEPD (.5% Yeast extract, 2% peptone, 2% glucose) agar plates

Sterile micro pipettes and tips (1000 mL and 200 mL)

Sharpie

Spreader bar

Klett Spectrophotometer

Ethyl alcohol

Burner

Sealed cardboard box with lid

3 cigarette brands (Marlboro, Camel Menthol, and Pall Mall were used in

this experiment)

Ash tray

Stop watch

Procedure1. Saccharomyces Cerevisiae was grown overnight in

sterile YEPD media.

2. The culture was placed in an incubator (30o C) until a density of 50 Klett spectrophotometer units were reached. This represents a density of approximately 107 cells/mL.

3. The culture was diluted in sterile dilution fluid to a concentration of 105 cells/mL.

4. 100µL of cell culture was then added to the test tubes, yielding a final volume of 10mLs and a cell density of approximately 103 cells/mL.

Procedure (Continued)

5. The solution was mixed by vortexing and allowed to sit at room temperature for 15 minutes.

6. After vortexing to evenly suspend cells, 100µL aliquots were removed from the tubes and spread on YEPD agar plates.

7. The plates were exposed to cigarette smoke for different time increments.

8. The plates were incubated at 30o C for 48 hours.

9. The resulting colonies were counted. Each colony is assumed to have arisen from one cell.

Marlboro Camel Menthol

Pall Mall Control0

20

40

60

80

100

120

140

160

180

200 1 minute ex-posure

Smoke Effects On Survivorshiop

Colonies

Overall P value: 2.11

1 min P value: .0022 min P value: .0001

Dunnett’s Test Table

Group T value Interpretation

Marlboro 1 minute

2.66 Significant

Marlboro 2 minutes

3.97 Not Significant

Menthol 1 minute

4.11 Not Significant

Menthol 2 minutes

4.98 Not Significant

Pall Mall 1 minute

4.51 Not Significant

Pall Mall 2 minutes

4.84 Not Significant

T Crit=3.49

Conclusion In conclusion the data shows that cigarettes were damaging

in both high and low concentrations.

This change was not significant between brands and times

as indicated by the 1 and 2 minute P values.

The overall P value indicates that there is a significant

change between the control and the variable groups.

This data supports the alternative and refutes the null.

Limitations and Extensions

This experiment could be extended in order to find a way to

repair the damage caused by smoke.

More brands could be tested.

More time increments could be tested

Different number of cigarettes

Could be tested on macro organisms

ReferencesGazdzinski, Stefan. "Cigarette Smoking Exacerbates Alcohol-Induced Brain Damage". Science Daily. 12/23/09 http://www.sciencedaily.com/releases/2004/12/041220004610.htmMartin, Terry. "The Effects of Smoking on Human Health". About.com. 12/23/09http://quitsmoking.about.com/od/tobaccostatistics/a/CigaretteSmoke.htmMartin, Terry. "What's in a Cigarette". About.com. 12/23/09http://quitsmoking.about.com/cs/nicotineinhaler/a/cigingredients.htmMultiple Authors. "Smoking Overview". Healthcommunities.com. 12/23/09http://www.cardiologychannel.com/smoking/index.shtmlMultiple Authors. "Yeast: Life Cycle and Reproduction". Biochemie.web. 12/23/09http://biochemie.web.med.uni muenchen.de/Yeast_Biol/10%20Yeast%20Growth%20and%20the%20Cell%20Cycle.pdfMultiple Authors. "Yeast". Wikipedia. 12/23/09 http://en.wikipedia.org/wiki/Yeast Not Given. "Secondhand Smoke". American Cancer Society. 12/23/09http://www.cancer.org/docroot/PED/content/PED_10_2X_Secondhand_Smoke

Clean_Indoor_Air.aspNot Given. "What is Menthol". Wise geek. 12/23/09 http://www.wisegeek.com/what-is-menthol.htmYi, John. "The propitious effects of antioxidants in preventing free-radical cell damage". Colorado-Wyoming Academy of Science. 12/23/09 http://www.highbeam.com/doc/1G1-89646548.html