18 Most VSAQ’s of Animal Diversity – I Chapter in Inter 1st Year Zoology (TS/AP)

Table of Contents

2 Marks

VSAQ-1 : What are the functions of canal system of sponges?

The canal system in sponges serves three essential functions

  1. Collecting and Distributing Food Particles for Nutrition: It is responsible for gathering and transporting food particles to different parts of the sponge’s body, ensuring proper nutrition.
  2. Facilitating the Exchange of Gases for Respiration: The canal system allows for the exchange of gases, enabling respiration in sponge cells.
  3. Removing Wastes from the Sponge’s Body for Excretion: It aids in eliminating waste products, supporting the process of excretion.

VSAQ-2 : What is metagenesis? Animals belonging to which phylum exhibit metagenesis?

Metagenesis refers to the occurrence of alternating sexual and asexual phases in the life cycle of an organism. This phenomenon is observed in animals belonging to the phylum Cnidaria, including creatures like jellyfish and corals.

VSAQ-3 : What are the excretory cells of flatworms called? What is the other important function of these specialized cells?

The excretory cells in flatworms are known as flame cells or protonephridia. These specialized cells serve the primary function of excretion, which involves removing metabolic waste from the flatworm’s body. In addition to excretion, flame cells also play a crucial role in osmoregulation, helping maintain the balance of water and salts within the flatworm’s body.

VSAQ-4 : Distinguish between amphids and phasmids.


  1. Location: Amphids are cuticular depressions around the mouth of nematodes.
  2. Function: They serve as chemoreceptors, aiding nematodes in sensing chemical cues in their environment.


  1. Location: Phasmids are posterior unicellular glands found in some nematodes.
  2. Function: They function as glandulo-sensory organs, potentially involved in various sensory functions, including chemoreception.

VSAQ-5 : What is botryoidal tissue?

  1. Botryoidal tissue is a distinctive tissue found in leeches.
  2. It occupies the entire coelom and resembles a cluster of grapes.
  3. Botryoidal tissue serves multiple functions in leeches, including excretion, storage of iron and calcium, and revascularization in areas of injury.

VSAQ-6 : Which arthropod, is called a ‘living fossil’? Name its respiratory organs?

The arthropod known as a “living fossil” is Limulus, commonly known as the king crab. Its respiratory organs are called book gills.

VSAQ-7 : What is the function of radula? Give the name of the group of molluscs which do not possess a radula?

  1. The function of radula is to serve as a rasping organ in molluscs, primarily used for feeding and scraping food.
  2. The group of molluscs that do not possess a radula is Bivalvia or Pelecypoda.

VSAQ-8 : What is Aristotle’s lantern? Give one example of an animal possessing it?

Aristotle’s lantern is a complex feeding structure comprising five jaw-like structures situated in the buccal cavity of sea urchins. An example of an animal possessing Aristotle’s lantern is Echinus, a type of sea urchin.

VSAQ-9 : What is the essential difference between the larvae and adults of echinoderms, symmetry wise?

The essential difference in terms of symmetry between the larvae and adults of echinoderms is that the larvae exhibit bilateral symmetry, while the adult echinoderms exhibit pentamerous radial symmetry.

VSAQ-10 : What are the two chief morphological ‘body forms’ of cnidarians? What are their chief functions?

Nidarians have two main body forms

  1. Medusa Form: Primarily for reproduction, with a bell-shaped body.
  2. Polyp Form: Mainly for nutrition, featuring a tube-like structure.

VSAQ-11 : What do you call the locomotor structures of Nereis? Why is nereis called a polychaete?

The locomotor structures of Nereis are termed parapodia. Nereis is called a polychaete because each parapodium contains multiple setae (bristles) – “poly” meaning many, and “chaeta” meaning setae.

VSAQ-12 : What do you call the first and second pairs of cephalic appendages of a scorpion?

The first pair of cephalic appendages of a scorpion is called chelicerae, and the second pair is called pedipalps.

VSAQ-13 : What are the respiratory structures of Limulus and palamnaeus respectively?

  1. The respiratory organs of Limulus are book-gills (aquatic).
  2. The respiratory organs of Palamnaeus (scorpion) are book lungs (aerial).

VSAQ-14 : What are antennae? What is the arthropod group without antennae?

  1. Antennae are tactile sense organs in arthropods, often used for sensing their environment.
  2. The arthropod group without antennae is the Subphylum Chelicerata.

VSAQ-15 : What is the other name for the gill of a mollusc? What is the function of osphradium?

  1. The other name for the gill of a mollusc is ctenidium.
  2. Osphradium is a water-testing organ found in bivalves and gastropods. Its primary function is to detect changes in water quality and to be involved in chemoreception.

VSAQ-16 : What are spermathecae on the body of pheretima?

Spermathecae in the body of Pheretima are sperm-storing organs, and there are four pairs of them.

  1. One pair is located in each of the 6th, 7th, 8th, and 9th segments.
  2. They receive sperms during copulation for later use in reproduction.

VSAQ-17 : What do you call the perivisceral cavity of an arthropod? Where from is it derived during development?

The perivisceral cavity of an arthropod is referred to as the haemocoel. It is not a completely true coelom. It is primarily derived from the blastocoel during development and is filled with blood.+

VSAQ-18 : What are blood glands in pheretima?

Blood glands in Pheretima are located in the 4th, 5th, and 6th segments. Their primary function is to produce blood cells and haemoglobin, which is dissolved in plasma.