Ask Mr. Brain ... all will be explained

PUBLISHED : Friday, 26 March, 1999, 12:00am
UPDATED : Friday, 26 March, 1999, 12:00am

Europeans have many different surnames. What is the origin of them? JANE WONG Marymount Secondary School Unlike the Chinese, who have only a few hundred, Europeans have tens of thousands of surnames.

While in Hong Kong it is common to have two or more classmates who share the same family name, in Europe it is very unusual.

Surnames didn't really catch on in Britain until about 600 years ago. Presumably the increase in population started to make it necessary to distinguish between the Johns or Marys. British surnames, like many in Europe, have a variety of origins.

Places, trades and personal appearance all have names based on them. Many surnames given to people were simply the name of the village or town they came from or were associated with. Other names came from features of the countryside, such as Wood, Hill and Brook.

The most common British surname is Smith, which comes from blacksmith, the rural metal workers common to villages until this century. Other names associated with occupations include Miller, Taylor (tailor), Farmer and Tanner.

Many British names end in -son, such as Jackson, Harrison and Johnson which indicate son of. So 'Jackson' was originally 'Jack's son'. The Scottish Mc- and Irish Mac- and O'- also indicate son of.

Names such as Brown, Black, Sharp and Wise usually come from personal characteristics attributed to the first holder of the name.

Many names have meanings which have been lost or forgotten.

For example, Kennedy comes from the Gaelic for 'ugly head', a meaning sadly lost on the vast majority of people who are not familiar with Gaelic.

How does food give us energy? SIMON NG SHIU-CHUNG La Salle College Food is converted into energy through digestion. In the process, food is broken down into a form capable of being absorbed into our bodies and converted into energy.

Digestion usually involves two processes - a mechanical one and a chemical one.

The mechanical part includes tearing and chewing by teeth, crushing and grinding by mouth, and churning by the stomach.

Chemical aspects of digestion often begin in the mouth when enzymes in the saliva begin to break down the food into simple molecules of sugars, fats or proteins.

Humans rely on a supply of special juices from the stomach (gastric juice), pancreas (pancreatic juice) and liver (bile) for chemical digestion. Proteins, starch and fats are broken down to be absorbed by our bodies and provide us with energy.

Mitochondria play an important role in digestion.

They are minute, cigar-shaped structures found in the cytoplasm of all cells except those of bacteria and blue-green algae. About 0.003 milli metres long, they are the site of a vital process called respiration, in which energy is directly released for the cell's needs.

If a person does not have enough mitochondria in his body's cells, he will get tired easily and suffer a lack of energy.