The sperm and the egg make different contributions to zygote. Which of the following statements about their contributions are true?
(i) Sperm contributes most of the mitochondria.
(ii) Egg contributes most of the cytoplasm.
(iii) Both sperm and egg contribute haploid nucleus
(iv) Both sperm and egg contribute centrioles.
(ii) and (iii)
Egg is larger in size as compared to the sperm, therefore, it contributes most of the cytoplasm, including the mitochondria, during fertilization. Only sperm head containing nucleus enters egg during fertilization. Haploid nucleus is contributed by both sperm and egg.