Among Nature’s most intriguing phenomena are the partnerships formed by any different species. The name used for these relationships, Symbiosis, comes from Greek meaning "living together". Not all symbiotic relationships are the same. There are some called commensal relationships, in which one partner gains a benefit while the other gains little or none but is not harmed. One example is the relationship between two types of fish remoras and sharks. The remora, which is long and often striped, attaches itself to a shark (sometimes to another type of fish or a whale), using a sucker on its head. When the shark makes a kill, the hitchhiker briefly detaches itself to feed on the scraps. Another type of symbiotic relationship is parasitism, in which one partner benefits at the expense of others. Ticks and tapeworms are among familiar parasites. 

The third type of symbiotic relationship, called mutualism, is a true partnership in which both partners benefit. The relationship may be limited as when zebras and wild best graze together on the vast African grasslands. Each species can survive on its own, but together their chances of detecting predators are improved because each contributes a specially keen sense. (Zebras have the better eyesight;  wild beast, hearing and sense of smell). In a few cases partners are so interdependent that one cannot survive without the other. Most mutualistic relationships probably lie some where in between

Remora attaches itself to the shark or whale 

Replace the underlined part of the sentence with one word from the options given below:
 John is a person who collects stamps.

Which one of the following is the correct meaning of -
 The study of human behaviour and societies:

Which one of the following is the correct meaning of -
 Killing of self -

Which one of the following is the correct meaning of -
 That which cannot be heard.

Which of the following is the synonym of Indict? 

Which of the following is the synonym of HASTE?

_______ teachers prefer a class that is fairly consistent in having pupils of the same level.