Question

Q4. Answer the following questions:
1. Why do organisms need to take food?
2. Why is the sun considered as ultimate source of food?
3. If a piece of chapatii is chewed for some time without swallowing it taste sweet why?
4. What is relation between joules and calo: jes? And convert 4.2cal to joules?
5. Write the melting and boiling point of water in Celsius and Fahrenheit?
6. In winter why metallic handles of wooden doors are colder.
Why eskituos make double walled house of blocks of ice?
8. Wny exhaust fans are placed near roof?
9. Why fire fighters wear shining suits and 1.elmets?
10. It is easier to drink tea from the porcelain inug than from a steel glass?
11. Why ice blocks are covered with jute sacks during transfer?
12. Why deserts are hot at day and cool at night?
13. Explain construction and working of therr hos flask?
14. What is difference between xylem and phloem?​

Answer 1

1. organisms need food to stay alive.
2. because sun light contains vitamin D
3. It is because saliva is mixed in it.