Fill in the blanks `:` (i) Variability of animals `"….............."` has greatly helped in their classification. (ii) Heterotrophic mode of nutrition is an important factor in causing great diversity in the `"…................"` of animal structure. (iii) Fertilization results in the formation of `"..................."` zygote. (iv) The digestive cavity of Hydra has only `"..............."` opening for both ingestion and egestion. (v) Radial symmetry means that the body of the animal may be divided into `"..................."` equal halves.

Fill in the blanks `:` (i) Variability of animals `"….............."

1.	Fill in the blanks `:` (i) Variability of animals `"….............."` has greatly helped in their classification. (ii) Heterotrophic mode of nutrition is an important factor in causing great diversity in the `"…................"` of animal structure. (iii) Fertilization results in the formation of `"..................."` zygote. (iv) The digestive cavity of Hydra has only `"..............."` opening for both ingestion and egestion. (v) Radial symmetry means that the body of the animal may be divided into `"..................."` equal halves.
Answer» (i) Morphyology (ii) Gut or digestive system. (iii) Diploid (iv) Single ( mouth ) (v) Two.