Colour Changing Milk & Drinking Bird

Here is a workshop report that I've done. The workshop is called "Science for Fun" and is organized by Hwa Chong Institution (High School).

Click here to view the report.

What are corns and callus?

I'm writing this as there is a very tiny corn on my foot. Therefore, having experienced a callus before, I sought treatment quickly. Curious, I decided to research on the theory behind callus.

Overview

A callus (tyloma) is an area of skin that thickens after exposure to repetitive forces in order to protect the skin. A callus may not be painful. When it becomes painful, treatment is required.

When a callus develops a mass of dead cells in its center, it becomes a corn (heloma). Corns generally occur on the toes and balls of the feet. Calluses occur on the feet, hands, and any other part of the skin where friction is present.

A corn or callus are areas of thickened skin that occur in areas of pressure. They are actually a normal and natural way for the body to protect itself. For example, callus develops on the hand when chopping a lot of wood. In the foot, the skin will thicken up to protect itself when there are areas of high pressure. The problem occurs when the pressure continues, so the skin gets thicker. It will eventually become painful and is treated as something foreign by the body.

Too much pressure can be from causes such as:

• Footwear that is too tight (Most common)
  
• Toe deformities, such as hammer toes - the top of the hammer toe is an area for increased pressure on the top of the toe
• Bony prominence
• Biomechanical or gait abnormalities that cause pressure under different areas of the bottom (plantar) surface of the foot (this is a common cause of callus)

Using remedies such as corn paint, cure or plasters will generally only treat the symptom of the corn and not the problem that causes it. These chemicals contain acid that are supposed to 'eat away' the corn, but the chemical can not tell what is corn and what is normal - it will eat what ever you put it on. As a result, the corn will come back again. To prevent it, it is recommended that you trace back to the root cause of the corn.

References

• http://www.epodiatry.com/corns-callus.htm
• http://www.emedicinehealth.com/corns_and_calluses/article_em.htm
  

Why is the sea blue?

The sea is blue mainly because:

• The sea reflects light from the sky.
• Although some scientists don;t agree with this, water reflects and scatters the light that strikes it. This can be shown by your reflection in the water . When the sky is brilliant blue, the sea is also blue, because it reflects the blue of the sky.

• The sea refracts light like the sky.
• Blue light is more easily bent, or refracted, than red light.Therefore, light refracted back from the surface of the sea appears to be blue. When you are underwater the water around you appears blue because more blue light is scattered back to your eye than red light.

This is a good cite for the answer: http://www.madsci.org/posts/archives/dec96/848799227.Es.r.html

Visit this cite for more information on why the sea might appear green too: http://answers.yahoo.com/question/index?qid=1006022203440

References

• http://www.madsci.org/posts/archives/1998-02/887691022.Bc.r.html
• http://answers.yahoo.com/question/index?qid=1006022203440
• http://www.enotes.com/science-fact-finder/earth/why-sea-blue