1. Atoms and Molecules Atoms and molecules designs how matter behaves
Example : Properties of water molecule determines how water behaves, properties of sugar molecules determines how sugar behaves

2. Hemoglobin Oxygen carrying protein in blood Normally binds to oxygen
Can also bind to CO molecules
Show image from text book

3. Atoms and Molecules Atoms are the building blocks of matter
Free atoms are rare in nature
Atoms bind together specific geometrical arrangement called molecules
Example – Carbon and oxygen combine together to form CO molecule which
can easily bind inside hemoglobin
CO poisoning , CO fits inside hemoglobin, breathing air containing CO dimnishes the oxygen carrying capacity of blood and can lead to death.sho and w models of CO,CO2 and H2O

4. Discussion Why CO is more toxic than CO2 ?
Group discussion

5. Scientific Method Observation of an experiment
Hypothesis – can be confirmed by experiments
Series of similar observation leads to a law
Scientific law describes how nature behaves
Scientific theory explains why nature behaves

6. Scientific Theory