lick the most appropriate answer
1. Which of the following is a clearer vehicle fuel?
2. Which of the following uses reduces the oxygen carrying capaoty of blood?
NO
3. The water from a water body in which untreated domestic sewage is discharged causes
(b) typhoid
4. The excessive growth of algae in ponds/takes due to excessive deposition of fertilisers. Desde
called
(a) autophosion (b) saponification
(c) chination
(one
5. Which of the following is not a chemical pollutant of water?
2) Pesticides
(b) Bacteria
(c) Perier
d) Mercury
6. Acid rain is caused by
a NO
(6) SO
(a) Both (a) and (b) (d) None of the
7. Smog is a combination of
(a) smoke and fire (b) fire and water
(c) smoke and top d) None of
8. Ozone layer is depleted by emission of
(a) CFCS
(b) SO
(c) CO
(0) CO
9. Greenhouse effect is caused by
(a) UV rays
(b) green lights of spectrum (c) X-rays
(6) All of the
10. Potable water can be purified by
(a) using water filter
(b) boiling
(c) adding chlorine (d) All of these
Answers
Answer:
During gas exchange oxygen moves from the lungs to the bloodstream. At the same time carbon dioxide passes from the blood to the lungs. This happens in the lungs between the alveoli and a network of tiny blood vessels called capillaries, which are located in the walls of the alveoli.The circulatory system is made up ofblood vessels that carry blood away from and towards the heart. Arteries carry blood away from the heart and veins carry blood back to the heart. Thecirculatory system carries oxygen, nutrients, and hormones to cells, and removes waste products, like carbon dioxide.A body system is a collection of parts able to work together to serve a common purpose – growth, reproduction and survival. ... The human body is made up of a number of inter-related systems that work together to maintain a stable internal environment. Cardiovascularsystem. The heart and blood vessels make up this system