1. Which is a by-product of photosynthesis ?   Nitrogen   ATP   Carbon dioxide   Oxygen   Hint Half-n-half Clue   2. Interaction between organisms of different species so as to get benefit from each other is known as   Symbiosis   Predation   Etiolation   Saprophytism   Half-n-half Clue   3. What is quinine used for ?   Curing Malaria   Removing pimples   Curing Typhoid   Curing Aids   Half-n-half Clue   4. Which is not a 'renewable' resource of energy ?   Water   Sun   Wind   Petroleum   Half-n-half Clue   5. Saprophytes derive their food from dead organisms.   False   True   6. 'Lac' is a plant product.   True   False   7. Which is not true regarding parasites ?   They derive their food from the organism on which they live.   They are always beneficial to the other organism.   Leech is a parasite.   They live on or inside the other organism.   Half-n-half Clue