Friday, February 17, 2012

The Effects of Cigarettes Smokes on Your Lungs

The school project to observe the effects of cigarettes smokes on lung is give to students at the age of 15 years in public schools in Malaysia. One of the objective of the ministry is to smoke clean living without tobacco.

Aim:
To observe the effects of smoking on the lungs.

Apparatus and Materials:
Thermometer, U-tube, cotton wool, rubber tubing, glass, glass tubing, conical flask, filter pumps, cigarettes, litmus paper, rubber stopper, lighter or match.

Procedure:

1. The apparatus to be set up as in the Figure 1

2. The following data are recorded before and after the activities
a. the color and smell of the cotton wool
b. the color of the litmus paper solution
c. the temperature of the u-tube

3. The cigarette was lit.

4. The filter pump was switched on.

Observation

Substances
Observations
Inference
Cotton Wool
The white cotton wool turns brown
Cigarette smokes contains tar.
Universal  Indicator
The solution turns from green to yellow
Cigarette smoke contains acidic gases
Thermometer
The temperature rises from 30 to 32 degrees C
Cigarette  smoke  produces heat









Questions

1. What does the cotton wool in the u-tube represents?.
It represents the human lungs.

2. What is the function of the litmus paper solution?.
It is an indicator to test the acidity or alkalinity of the smoke.

3. What is the materials in the smoke that cause the cotton wool to change color?.
The materials are the nicotine and tar.

4. What cause the litmus solution to change its color?.
sulphur dioxide, carbon monoxide and hydrogen cyanide.

5. What is the conclusion of the experiment?.
The cigarette smoke contains harmful substances that can cause diseases such as bronchitis, asthma, lung cancer and heart disease.

Youtube Video
I am searching for free video to supplement the above experiement.

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Wednesday, February 8, 2012

Science Project: Breathing Mechanism

One of the project for form 3 science project in Malaysia is on the Breathing Mechanism.

AIM
The aim of the project is to build a functional model of the human respiratory system, to show the relationship between the air pressure in the thoratic cavity and the breathing mechanism.

APPARATUS AND MATERIALS:
Bell jar, Y-shaped glass tube, conical flask, rubber stopper, syringe, thin rubber sheet and balloon.

PROCEDURE
1. A model of the respiratory system was built as shown in the figure a below.

2. The rubber sheet was pulled down and what happened in the bell jar was observed and recorded.

3. The rubber sheet was pushed upwards into the jar and what happened to the balloons was observed and recorded.

OBSERVATION


what
is done
changes
in balloon
pressure
in the bell jar
inference
1 rubber
sheet was pulled down
The
balloons inflate
Air
pressure decrease
higher
air pressure caused the balloons to inflate
2 rubber
sheet pushed up
the
balloons deflate
the
air pressure increase
the
higher pressure in the jar pushed the air in the balloon out


DIAGRAMS


These were the questions given to the students after the experiement.

1. Name the parts of the respiratory system represented by the:
a. bell jar         ---> thoraicic cavity
b. the y-shaped glass tube -----> brochi
c. the balloons ----------------> lungs
d. rubber sheet ---------------> diaphragm

2. The lower diagram shows another project model that can be used to show the human breathing mechanism. Explain what happen?.
a.When the plunger of the syringe is pulled up, the air pressure in the jar reduced and the balloon will inflate.
b. When plunger is pushed down, the pressure will increase causing the balloon to deflate.

3. What is the relationship between the air pressure in the thoracic cavity and the breathing mechanism?.
As the air pressure in the thoracic increases, air is forced out of the lungs. This is called exhalation.
As the as air pressure in the cavity reduces the ambient air will rush into the lung, this phase is called inhalation.

CONCLUSION
The inflation and deflation of the lungs is caused by the movement of the thoracic diaphragm.

VIDEO from YOUTUBE

Tuesday, February 7, 2012

Form 3 Questions

In the school today, we did not have any experiment or project.

We had started a new topic.. the human respiratory system. So the teacher gave some questions to do:

1. Name the structures of the respiratory system:
- nasal cavity
- trachea
- ribs
- intercastal muscles
- bronchus
- bronchioles
- lungs
- diaphragm

2. How is the respiratory system protected?
It is protected by the ribs cage

3. What will happen if a rib breaks and punctures the lung?
Without immediate medical attention, he will die/

In Malaysia form 3 is for the age of 15 years. there is a national examination at the end of the year. The exam is called PMR.