GSEB Solutions for Class 8 Science and Technology – Microbes (English Medium)
|Name of the Disease||Causes||Symptoms||Precautions||Is any microorganism responsible for that? If yes, then which one?|
|Measles||Air||High temperature, Sore eyes, dry cough||Vaccination at proper age||Yes, virus|
|Hepatitis A||Water||Fatigue, urea, dark urine||Drinking boiled water, vaccination at proper age||Yes, virus|
|Typhoid||Water||Poor appetite, lethargy, diarrhoea||Drinking purified water, vaccination||Yes, bacteria
|Malaria||Mosquito bite||Fever, Chill, Fatigue||Applying mosquito repellants, mosquito nets and proper dosage of medicines||Yes, protozoa|
|Polio||Air/ Water||Fever, Sore throat, Vomiting, Fatigue||Proper vaccination||Yes, Virus (Poliomyelitis)|
|Tuberculosis||Air||Bad cough for three weeks, weight loss, no appetite, chills||Vaccination of BCG||Yes, bacteria (Mycobacterium)|
|Chickenpox||Air/ Contact||High temperature, loss of appetite, spots in the body leading to itching||Antibiotics and proper vaccination||Yes, Virus|
The microorganism is a living organism that requires a microscope to be observed as it cannot be seen with naked eyes.
The types of microorganism are bacteria, virus, fungi, algae, protozoa and fungi.
The algae is different from other plants in the following ways:
- Most algae are single celled.
- They are motile by using their cilia or flagella.
- They do not have true roots, shoots or veins.
- Algae engage all the water and nutrients they need.
There are two main types of fungi – yeast and mould.
The two diseases caused by bacteria are cholera and tuberculosis.
The two diseases caused by virus are polio and chickenpox.
Algae prefer moist places like ponds, sewages, reservoirs, rivers, swamps, lakes, and mud. They also grow on marine animals like alligators, worms and aquatic plants.
There are three types of colours found in algae – brown algae, blue-green algae and red algae.
Brown algae are found near coral reefs, blue-green algae are found in freshwater lakes, streams and ponds, red algae can be found anywhere on the earth ranging from the tropical region to the polar region.
The reserved food material of the fungi is on dead materials like roti, pickles, wet clothes and leather goods.
Amoebic dysentery is caused by protozoan, Entamoeba histolytica
An amoeba has no definite shape. It can move anywhere with the help of cilia and flagella.
Paramoecium has the definite shape of a slipper (shoe) and moves with the help of cilia.
Virus is called the connecting link between living and non-living because it possesses both living and non-living characteristics. The living characteristics are as follows –
- They can reproduce.
- They contain genetic matter.
- They are also locomotive.
The non-living characteristics are as follows –
- They cannot replicate alone.
- They remain inactive and behave as non-living.
Most microorganisms are beneficial, for example, there are microorganisms in our large intestine that synthesize vitamins and allow them to be absorbed into the bloodstream. However, a tiny minority are pathogens (disease-causing agents). These pathogens, often called germs or bugs, are a threat to all life forms.
he virus in tobacco is Tobacco Mosaic Virus (TMV)