(i) Long nails can cause diseases to us. Because, the microbes present in the dirt deposited under the long nails go inside our body while we are eating and can cause diseases.
(ii) We should properly cut our nails regularly, as nails keep on growing.
(iii) (a) I will keep an eye on the nails of my youngers, friends and relatives and persuade to cut nails regularly to those who keep long nails than desired.
(b) I along with my friends, teachers and NGOs organise lectures and discussions, especially in nearby rural areas, to educate people in this regard.

(i) Ostrich (Struthio cametus), its egg size is about 15 em x 13 cm weighing about 3 pounds.
(ii) An egg provides sufficient proteins, fats, vitamin A and vitamin D.
(iii) Eggs contains lot of cholestrol that may cause heart diseases. We should not eat many eggs in a day for long period.
(iv) Our duty is that we should make our friends, relatives and community to know about useful and harmful effects of eating eggs.

(i) Plants also formed of cells like us or other animals.
(ii) Plants are also living things. We should not harm them unnecessarily, rather we should protect them.

(i) Lysosomes contain powerful digestive enzymes capable of breaking down all organic material.
(ii) Lysosomes help to keep the cell clean by digesting worn out cell organelles and foreign material such as bacteria or food.
(iii) RER (Rough Endoplasmic Reticulum) makes the digestive enzymes present in the lysosomes.

Viruses lack selectively permeable plasma membrane and cell organelles.

Thus they lack a basic structural organisation to perform various life processes effectively and in their own way.

After entering a living cell, a virus utilises its own genetic material and machinery of host cell to multiply.

The part of protoplasm which remains after excluding nucleus is known as cytoplasm. Cytoplasm contains aggregate molecules of various chemicals and cell organelles. Most of the biochemical reactions such as protein synthesis, release of energy etc. take place in cytoplasm or organelles present in the cytoplasm.

Difference

Example of osmosis:
(i) Absorption of water by plant roots.
(ii) Absorption of water by freshwater unicellular organisms such as Amoeba.

(i) Extracellular digestion. Sometimes lysosome enzymes are released outside the cell to break down extracellular material.
(ii) Digestion of foreign material. lysosomes also destroy and foreign material which enters inside the cell such as bacteria.
(iii) Cellular digestion. In damaged cells, ageing cells or dead cells lysosomes get ruptured, and enzymes are released. These enzymes digest their own cell.
Lysosomes contain about 40 hydrolytic enzymes. When the cell gets damaged, lysosomes burst and their enzymes digest their own cell. So, lysosomes are called 'suicide bags'.
Foreign materials entering the cell, such as bacteria or food, as well as old organelles end up in the lysosomes, which break them up into small pieces.

1. Lipids and proteinsconstituting the cell membrane are synthesized in the endoplasmic reticulum.
2. SER (Smooth endoplasmic reticulum) helps in the manufacturing of lipids.
3. RER (Rough endoplasmic reticulum) has particles attached to its surface, called ribosomes. These ribosomes are the site for protein synthesis.

(i) Lysosomes are membrane-bound sacs filled with digestive enzymes.These enzymes are made by rough endoplasmic reticulum.
(ii) Lysosomes are a kind of waste disposal system of the cell.
(iii) During the disturbance in cellular metabolism, e.g. when a cell gets damaged, lysosomes present in the cell may burst and the enzymes digest the damaged cell. Hence, lysosomes are called as 'suicidal bags' of a cell.
(iv) Lysosomes break up the foreign materials entering into the cell, such as bacteria or food into smal piece

(i) We will give ORS (Oral Rehydration Solution) from time to time till we reach to doctor or doctor comes to attend the patient. ORS is available in powder form packed in sachets.
(ii) We can make ORS in home by the following way:
Ingredients
1. One level teaspoon of salt
2. Eight level teaspoon of sugar
3. One litre of clean drinking or boiled water and then cooled (5 cupfuls-each cup about 200 .ml.),
Preparation Method
Stir the mixture till the salt and sugar dissolve.
(a) Arrange community lectures, debates to sensitise harmful effects of dehydration of the body.
(b) Conveying importation of ORS and its preparation in home