UNIT 1 : MICROORGANISMS

At the end of this unit, we will learn:• The different types of microorganisms.

• About Life processes that microorganisms and their harmful effect.

• The use of microorganisms and their harmful effects.• How diseases caused by microorganisms can spread.

• Ways to prevent diseases caused by microorganisms from spreading

LESSON 1 : THE UNSEEN LIFE

All living things are created by God. Humans, animals and plants are living things. They are vary in size and can be seen with naked eyes. However there are tiny living things that can only be seen through a microscope. There are called microorganisms.

There are different types of microorganisms. They are bacteria, protozoa, fungi and virus.

Bacteria exist in different shapes, sizes and colours.

Most protozoa are found mainly in ponds,

lake and rivers. Some of them eat other microorganisms as food.

Fungi can be found on mouldy bread, rotten food, trees and forest floors.

Virus is the tiniest microorganisms. It can be found living in some bacteria, fungi, protozoa, animals, plants and humans.

LESSON 2 : FRIENDS OR FOESMicroorganisms can be very useful in our daily lives.

•Tapai is a popular food in Malaysia. It is made from glutinous rice or tapioca. Yeast is added to make Tapai.•Yeast is also used t help dough to rise in making bread.•Tempe is another kind of food that uses yeast. It is made from soya bean. •Some bacteria can be used to make cheese and yogurt.•Fungi are used to produce antibiotics.

Microorganisms can be harmful too!

Some microorganisms that enter the body can cause illness.

Eating food contaminated with microorganisms can cause food poisoning.

Bacteria act on the food remains between the teeth. This produces acid which causes tooth decay.

Some diseases can easily spread from one person to another. They are called contagious diseases. Example are influenza, measles, mumps, conjunctivitis and chicken pox.

HOW DO DIESEASES SPREAD FROM ONE PERSON TO ANOTHER?

Through food and drink.Sneezing or coughing.Direct contract.Carried by mosquitoes or fly.Microorganism can also spread through the

air.

HOW TO PREVENT DISEASES FROM SPREADING?

Wash your hand before handling food especially after using the toilet.

Drink the water that has boiled because boiling kills microorganisms.

Cover your mouth when sneezing or coughing to prevent microorganisms from spreading into the air.

Do not share personel items such as toothbrush, towel and comb.

Cover your wound to protect it from infection.Put patient with contagious diseases such as dengue

fever, malaria, chicken pox, conjunctivitis or mumps into quarantine.