1. **Explain the process of dehydration.**

Dehydration is the process of removing water from a substance, often used to preserve food by inhibiting the growth of microorganisms.

2. **Name three antibiotics known to you.**

Penicillin, amoxicillin, and tetracycline.

3. **What are the symptoms of food poisoning?**

Nausea, vomiting, diarrhea, abdominal pain, and fever.

4. **Where are bacteria found?**

Bacteria are found everywhere, including soil, water, air, and inside the bodies of plants and animals.

5. **Explain the mode of nutrition in fungi.**

Fungi obtain nutrients through absorption by secreting enzymes that break down complex organic matter into simpler compounds.

II. LONG QUESTION ANSWER.

1. **What are microorganisms? Briefly discuss major group of microorganisms.**

Microorganisms are tiny living organisms that are often invisible to the naked eye. Major groups include bacteria, viruses, fungi, protozoa, and algae.

2. **What does a vaccine consist of? How does a vaccine work?**

A vaccine consists of weakened or killed pathogens, or parts of them, that stimulate the immune system to recognize and fight the disease without causing illness.

3. **Write the beneficial actions of:**

(a) **Bacteria:** Bacteria help in decomposition, nitrogen fixation, and production of antibiotics and fermented foods.

(b) **Fungi:** Fungi decompose organic matter, form symbiotic relationships with plants (mycorrhiza), and are used in the production of antibiotics and fermented foods.

4. **Describe nitrogen cycle with the help of a neat labelled diagram.**

The nitrogen cycle includes processes like nitrogen fixation, nitrification, assimilation, ammonification, and denitrification, converting nitrogen between its various chemical forms.

5. **What are the advantages of food preservation?**

Food preservation prevents spoilage, extends shelf life, reduces food waste, and ensures availability of food during off-seasons.