The phenomenon of radioactivity was discovered by

Two atoms are said to be isotopes if

Consider the following statements about Periyar E.V. Ramaswamy:

1. He was a politician, social activist and an important figure in the Dravidian movement in South India
2. He championed the cause of caste upliftment, nationalism and the rights of women
3. He was contemporary of the Maharashtran anti-caste reformer, Jyotiba Phule

Which of the statements given above is/are correct?

Match List I with List II and select the correct answer using the code given below the lists :

Arrange the following events that took place in the first decade of the 20th century in chronological order:

1. Indian National Congress, Bombay Session
2. Establishment of All India Muslim League
3. Partition of Bengal
4. Indian National Congress, Surat Session

Select the correct answer using the code given below

Which of the following statements about sexual reproduction in flowering plants are correct?

1. Stamen is present in the centre of a flower.
2. Stamen produces pollen grains in the ovary.
3. The swollen bottom part of carpel is the ovary.
4. The fusion of germ cells gives rise to zygote.

Select the correct answer using the code given below