12. Could the number of eggs or young ones produced by an oviparous and viviparous
1. What are the difficulties that you would face in classification of animals, if common
fundamental features are not taken into account?
2. If you are given a specimen, what are the steps that you would follow to classify
it?
3. How useful is the study of the nature of body cavity and coelom in the
classification of animals?
4. Distinguish between intracellular and extracellular digestion?
5. What is the difference between direct and indirect development?
6. What are the peculiar features that you find in parasitic platyhelminthes?
7. What are the reasons that you can think of for the arthropods to constitute the
largest group of the animal kingdom?
8. Water vascular system is the characteristic of which group of the following:
(a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordata
9. "All vertebrates are chordates but all chordates are not vertebrates". Justify the
statement.
10. How important is the presence of air bladder in Pisces?
11. What are the modifications that are observed in birds that help them fly?
JU
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mother be equal? Why?
Answers
Answer:
1- closely related species could get diff phylums if common fundamental features are not considered, the classification would be more complex and time taking which would complicate the process.
2- 1st -identification, 2nd- characterization , 3rd- nomenclature, 4th- classification.
3-by this character we classify animals into 3 classes -
ACEOLOMATES - body cavity absent and mesoderm lining absent
PSEUDOCOELOMATES- body cavity present but incompletely lined by mesodermal lining.
EUCOELOMATES- body cavity present and completely lined by mesodermal lining.
4-intracellular digestion occurs inside the cell while extracellular occurs outside the cell that is in digestive cavity. the latter one is a advanced feature.
5-in indirect development larval stages are formed while in direct development the zygote or embryo directly forms adult one without any intermediate larval stage.
6-high reproductive capability, simplified digestive system, hooks present.
7-hard exoskeleton made up of chitin, high reproductive capacity, lay thousands of eggs at a time
8-option c echinodermata. in porifera water canal system is present.
9-phylum chordata is divided into protochordata and vertebrata so vertebrata is a subclass of chordata. so we justify the statement.
10-it provides buoyancy which avoids sinking of pisces but it is only present in ostheicthythes.
11-pneumatic bones i.e. hollow bones which contribute to less body weight and feathers help them to fly.
12-No it can't be equal as the eggs are having high risk as compared to viviparous young ones so no of eggs produced are greater than young ones produced.