Question

Q. True or False: (1/2×10=5)

1. Fuel may be solid, liquid or gas.

2. A matchstick only contains white phosphorus.

3. Increase in nitrogen gas in atmosphere has led to ‘global warming’.

4. Unicellular organisms have one-celled body.

5. Muscle cells are branched.

6. The basic living unit of an organism is an organ.

7. Amoeba has irregular shape.

8. Dodo is an extinct species.

9. Those species which no longer exist on the earth are known as endemic species.

10. Private ownership is not allowed in the national parks.​

Answer 1

Answer:

1 false

2. false

3. true

4 true

5 false

6 true

7 false

8 false

9 true

10 true

Answer 2

Answer:

1. The fuel is a material which when once raised to its ignition temperature continues to burn if sufficient oxygen or air is available. The principle constituents of any fuel are carbon and hydrogen. Fuels may be solid, liquid or gaseous. They may be natural or artificially prepared.
2. Safety matches ignite due to the extreme reactivity of phosphorus with the potassium chlorate in the match head. When the match is struck the phosphorus and chlorate mix in a small amount forming something akin to the explosive Armstrong's mixture which ignites due to the friction.
3. Nitrogen (N) use in agriculture substantially alters global N cycle with the short- and long-term effects on global warming and climate change. It increases emission of nitrous oxide, which contributes 6.2%, while carbon dioxide and methane contribute 76% and 16%, respectively of the global warming.
4. Unicellular organisms have one-celled body. Muscle cells are branched. The basic living unit of an organism is an organ. Amoeba has a irregular shape.
5. There are many cells present in our body and some of the cells are branched but muscle cells is not one of them they form a Framework for our body. Instead of being branches there are basically spindle shaped, the Nerve cells on the other hand are the ones that are branched in our body.
6. Unicellular organisms have one-celled body. (True) Muscle cells are branched. ... The basic living unit of an organism is an organ.
7. Due to the presence of cells of irregular shapes, amoeba is irregular in shape. The shape of cells is related to its functions. These cells make crawling-type of movements by protruding their cytoplasm which results in the formation of irregular projections from its body called pseudopodia.
8. The dodo (Raphus cucullatus) is an extinct flightless bird that was endemic to the island of Mauritius, east of Madagascar in the Indian Ocean.
9. Species which are not extinct are termed extant. Those that are extant but threatened by extinction are referred to as threatened or endangered species.
10. A wildlife sanctuary is a protected area that is meant for the conservation of only fauna. Human activities like harvesting of timber, collection of minor forest products and private ownership rights are allowed as long as they do not interfere with the well-being of animals. Thus, the assertion is true but the give reason is incorrect.