question_answer 44)

  Differentiate between (a) Open circulatory system and closed circulatory system. (b) Oviparous and viviparous characteristic . (c) Direct development and Indirect development.

Answer:

                  Differentiation between these are as below

(a) Open Circulatory System	Closed Circulatory System
In this type of circulation, blood flows in spaces called sinuses and the cells and tissues are directly bathed in it. e.g., arthropods (grasshopper, cockroach), gastropods (snail).	In this type of circulation, blood is circulated via a series of vessels (arteries, veins and capillaries). e.g., annelids (earthworm) and vertebrates (birds, primates etc).
(b) Oviparous characteristics Animals	Viviparous Characteristic Animals
Oviparity is expulsion of undeveloped eggs rather than live young ones Animals that lay eggs. are called oviparous. e.g., fishes, reptiles, amphibians, birds, in sects and monotremes (mammals that lay eggs).	Viviparity is retention and growth of fertilized egg within the material body until the young one is capable of independent existence. Animals which give birth to their young ones and are called viviparous animals. e.g., mammals.
(c) Direct Development	Indirect Development
Direct development is the type of development in which there is no larval/nymphal or other intermediate stages in life, cycle between the egg (or birth) and the adult (e.g., mammals)	Indirect development is mostly observed in lower animals. The adult individuals lay eggs, which develop passing into the adult after passing through few to several larval nymphal stages, (e.g., echinoderms, arthropods)