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Amoeba – Protozoa ; 

Lactobacillus – Bacteria ; 

Chlamydomonas – Algae; 

Penicillium – Fungi ; 

Yeast – Fungi ; 

HIV – Virus

(a) Rust of wheat – Fungi 

(b) Citrus canker – Bacteria 

(c) Yellow vein mosaic of bindi (Okra) – Virus

(a) Foot and mouth disease is caused by a virus. 

(b) Anthrax disease is caused by a bacterium.

Cholera disease spreads through infected food or water.

D. increasing the fertility of soil 

Some of the micro-organisms are used to preparation of medicines. Some of microorganisms are used recycling of materials in nature and increasing the fertility of soil. The synthesis of food by photosynthesis takes place in leaves with the help of inorganic material like carbon-dioxide and water in the presence of sunlight and chlorophyll.

1. In two or three days. Observe these spots with the help of a magnifying glass.

2. Thin, white and black coloured patches are seen.

3. No, these structures are not seen without the magnifying glass.

4. These structures are the filaments and spores of fungi.

5. Spores of many micro-organisms remain suspended in air. In presence of favorable environment and nutrient, they grow and form filament – like structures.

1. Round, cylindrical, etc. shaped structures are seen.

2. These structures are micro-organisms.

Now a days, sterilized needles and syringes are used and they can be used only once.

1. We see node – like structures.

2. These node – like structures are called root nodes or nodules. Root nodules are formed on the roots of plants that associate with rhizobium bacteria.

3. They help in converting atmospheric nitrogen into nitrates.

4. No, they are found in the roots of leguminous plants.

Tuberculosis disease spreads by breathing in air containing micro-organisms.

The connecting link between living and non – living is Virus

1. They are rotten.

2. This is possible due to the preservation of food stuff.

Useful micro – organisms in our life are : 

1. Lactobacillus bacteria – Useful is making curd from milk. 

2. Rhizobium bacteria – It helps in fixation of nitrogen. 

3. Xenthomonas compestris – It is used to make tooth paste. 

4. Pencillium – Pencillin is used as a vaccine and antibiotic.

(a) Penicillin

(d) All of these

Rust of wheat is done by Fungi.

1. (b),

2. (a),

3. (d),

4. (c).

Amoeba is an unicellular organism.

(d) All of these

Tobacco Mosaic Virus.

Human Immuno Deficiency Virus

The different types of micro-organisms are :

Virus, bacteria, fungi, protozoa, algae and mycoplasma.

1. Micro-organisms

2. Yeast

3. Rhizobium

4. dehydration

1. Little leaf of brinjal 

2. Sesame phyllody

The carrier of parasite of malaria is Female Anopheles mosquito.

1. Spores 

2. parasites 

3. Penicillium 

4. Refrigeration

It is a technique of killing genus. Before packaging milk or other food items in cans or bottles, milk or the food items are heated at 60°C for 30 minutes and then cooled down. This process is repeated 2 – 3 times and it kills the harmful micro organisms present in them.

Some micro – organisms are harmful in the following ways :

1. Some micro – organisms cause disease like T.B., whooping cough, diptheria, tetanus, cholera, malaria, skin diseases etc.

2. Some micro – organisms spoil food stuff.

3. Some micro – organisms causes food poisoning. 

4. Some micro – organisms damage valuable items.

HIV is a Virus

Protozoa Plasmodium causes malaria disease.

Food poisoning is the process that makes food toxic. A bacteria called Clostridium botulinum, causes food poisoning and the person who eats this food suffers from vomiting and diarrhoea and in some cases, it may lead to death.

B. protozoan 

The malaria disease is caused by a protozoan called plasmodium.

Microorganisms such bacteria and fungi that grow on our food items sometimes produce toxic substances. These make the food unfit for consumption. Consuming such food can cause a serious illness called food poisoning.

We keep it in refrigerator.

B. sodium hydroxide 

sodium metabisulphate, sodium benzoate and citric acid are used as a food preservative whereas sodium hydroxide is not used as food preservative.

Food preservation: Processing of food to prevent their spoilage and to retain their nutritive value for period is called food preservation.

Food can be preserved using following methods: 

1. Preservation by Salt 

2. Preservation by Sugar 

3. Preservation by oil and vinegar 

4. Heat and cold treatment 

5. Storage and packing

We preserve cooked food in the refrigerator at home. Low temperature inhibits the growth of micro-organisms. When cooked food is kept in a cold place, then the food does not get spoiled easily.

All mosquitoes breed in water . Hence, one should not let water collect anywhere, in coolers, tyres, flower pot etc.

Rhizobium bacterium is found in the soil. It lives in the root nodules of leguminous plants such as beans and peas, with which it has  a symbiotic relationship . It is involved in the fixation of nitrogen in leguminous plants (pulses).

1. Yellow vein mosaic of bhindi (Okra) 

2. Citrus canker 

3. Rust of wheat

Sodium benzoate and sodium meta bisulphite are common preservatives which are used in the preservation of fruits as jams and jellies.

1. Poison

2. Bacteria 

3. Nucleoid 

4. Plasmid 

5. Yeast 

6. Mycology 

7. Zymase 

8. Anaerobic

i. c 

ii. d 

iii. a 

iv. b

Use of microbes to protect crops is called biocontrol

Example : Trichoderma (fungi) protects plant roots from pathogens.

Rhizobium is a nitrogen fixing bacteria.

1. e

2. d

3. b

4. c

5. a

Extra chromosomal DNA present in bacteria is called plasmid.

Probiotics :

Probiotics are live food  supplements use in yoghurt and other fermented milk products. 

Example: Lactobacillus acidophilus and Bifidobacterium bifidum. 

These bacteria improve the microbial spectrum in the gut and thus contribute to the following effects: 

1. Decrease the risk of colon cancer 

2. Decrease cholesterol absorption

3. Prevent diarrheal diseases by increasing the immunity power.

The nuclear content of a bacterial cell lacks nuclear membrane. So it is called nucleoid

1. Penicillin

2. Prions

3. Virion

4. Microscope

5. Monotrichous