1. Quinine is extracted from the bark of
2. What is hypertension?
(a) An increase in heart rate
(b) A decrease in heart rate
(c) A decrease in blood pressure
(d) An increase in blood pressure
3. _________are the contractile proteins present in muscle cells.
(a) Actin and Myosin
(b) Actin and Tropomyosin
(c) Myosin and Troponin
(d) Troponin and Tropomyosin
4. ________are the imaginary lines joining places with same cloud cover
5. A natural region has the similarity of
(a) climate and natural vegetation
(b) climate and occupation
(c) soil and drainage
(d) economic base and agriculture
6.Optical fibres are based on the phenomenon of
(d) Total Internal Reflection
7.Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
8.‘Mirage’ is an example of
(a) refraction of light only
(b) total internal, refraction of light only
(c) refraction and total internal reflection of light
(d) dispersion of light only
9.The phenomenon of light associated with the appear-ance of blue colour of the sky is
10.In which of the following areas, a spreadsheet software is more useful?
(d) Message sending