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

2 Marks

VSAQ-1 : List out the characters shared by chordates and echinoderms.

Shared characters of chordates and echinoderms

  1. Fate of Blastopore: Both exhibit deuterostome development.
  2. Radial and Indeterminate Cleavage: They undergo radial and indeterminate cleavage during embryonic development.
  3. Enterocoelom Formation: Both develop an enterocoelom derived from the archenteron.

VSAQ-2 : Write four salient features of cyclostomes.

Salient features of cyclostomes

  1. Jawless, Aquatic Organisms: Cyclostomes are jawless and primarily aquatic animals.
  2. Long, Slender, Scaleless Body: They possess a long, slender, and scaleless body, resembling eels.
  3. Round, Suctorial Mouth: Cyclostomes have a round, suctorial mouth equipped with a tongue bearing horny teeth.
  4. Two-Chambered Heart: Their circulatory system includes a two-chambered heart.

VSAQ-3 : What is the importance of endostyle in lancelets and ascidians?

  1. Mucous-Secreting Groove: It secretes mucus to trap food particles.
  2. Food Collection: Plays a crucial role in food collection.
  3. Precursor of Thyroid Gland: Considered the precursor of the thyroid gland in

VSAQ-4 : Name the type of caudal fin and scales that are present in a shark and catla, respectively.

  1. In sharks, the type of caudal fin is heterocercal, characterized by an unequal upper and lower lobe.
  2. In catla, the scales are cycloid scales, which are smooth-edged and overlapping.

VSAQ-5 : What is the importance of air bladder in fishes?

The importance of the air bladder in bony fishes includes:

  1. Hydrostatic Organ: It acts as a hydrostatic organ, enabling the fish to maintain buoyancy and stay at desired water depths with ease.
  2. Vertical Movement: The air bladder allows for vertical movement, enabling the fish to ascend or descend within the water column.
  3. Respiration: In some fishes, it may aid in respiration, assisting in the exchange of gases with the surrounding water.

VSAQ-6 : How do you justify the statement “heart in fishes is a branchial heart”.

The statement “heart in fishes is a branchial heart” is justified because the fish heart primarily pumps deoxygenated blood to the gills for oxygenation, emphasizing its role in branchial (gill) circulation.


VSAQ-7 : What are claspers? Which group of fishes possesses them?

Claspers are specialized copulatory organs found in male sharks. These structures are located near the pelvic fins and are used during mating to transfer sperm to the female shark’s reproductive tract. Claspers are unique to cartilaginous fishes, which include sharks, skates, and rays. They are essential for facilitating internal fertilization in these fishes.


VSAQ-8 : How does the heart of an amphibian differ from that of a reptile?

The heart of an amphibian has three chambers (two atria and one ventricle), while the heart of a reptile has four chambers (two atria and two ventricles). This difference allows reptiles to have a more efficient circulatory system with complete separation of oxygenated and deoxygenated blood, while amphibians have some mixing of blood in a single ventricle. The four-chambered reptilian heart is better suited for terrestrial life, providing greater metabolic efficiency and adaptability to varying environmental conditions.


VSAQ-9 : How do you distinguish in a male frog from a female frog?

To distinguish between a male and female frog:

  1. Check for size differences, with females often being larger.
  2. Examine the thumb pads on the inner digits; males have thicker pads.
  3. Look for nuptial pads on male forelimbs, used for gripping during mating.
  4. Observe vocal sacs that inflate when males call; females usually lack them.
  5. Note differences in the cloaca – males have a swollen, pronounced cloaca, while females have a smaller one.

VSAQ-10 : Distinguish between milt and spawn.

  1. Spawn: Spawn is the mass of eggs released by a female frog (or other lower aquatic vertebrates) during reproduction.
  2. Milt: Milt is the mass of sperm released by a male frog (or other lower aquatic vertebrates) during reproduction.

VSAQ-11 : Name two poisonous and non poisonous snakes found in south india.

Poisonous Snakes in South India

  1. Indian Cobra: Highly venomous with a distinctive hood.
  2. Russell’s Viper: One of the most dangerous snakes with potent venom.

Non-Poisonous Snakes in South India

  1. Indian Rock Python: A large, non-venomous constrictor snake.
  2. Common Sand Boa: Relatively small and harmless, feeding on small prey.

VSAQ-12 : Name the four extra embryonic membranes.

Four Extra-Embryonic Membranes:

  1. Amnion
  2. Allantois
  3. Chorion
  4. Yolk sac

VSAQ-13 : What are Jacobson’s organs? What is their function?

  1. Jacobson’s Organs: Jacobson’s organs are specialized olfactory structures found in snakes and some lizards.
  2. Function: Their primary function is to detect and analyze scent molecules in the environment. Snakes and certain lizards use their forked tongues to collect scent particles and then transfer them to Jacobson’s organs for sensory analysis. This unique capability aids them in identifying prey, predators, and potential mates by analyzing chemical cues in their surroundings.

VSAQ-14 : What are pneumatic bones? How do they help birds?

  1. Pneumatic Bones: Pneumatic bones are bones that contain air cavities.
  2. How They Help Birds: Pneumatic bones are a flight adaptation in birds. They serve to reduce the overall weight of the bird, making it easier to fly. Additionally, the air-filled bones provide buoyancy and improve the bird’s aerodynamic efficiency during flight, contributing to their ability to soar and maneuver effectively in the air.

VSAQ-15 : What is wish bone? What are the skeletal components that form it?

Wishbone (Furcula): In birds, the wishbone is a V-shaped bone formed by the fusion of two clavicles and an interclavicle. It acts as a spring, aiding in wing stability during flight.


VSAQ-16 : How does a mature RBC of a mammal differ from that of other vertebrates?

  1. Mature RBCs in Mammals: Mature red blood cells (RBCs) in mammals are circular, biconcave, and lack a nucleus.
  2. RBCs in Other Vertebrates: In contrast, RBCs in other vertebrates are oval, biconvex, and usually have a nucleus.

VSAQ-17 : Name the three meninges. In which group of animals do you find all of them?

  1. Three Meninges:
    • Dura mater
    • Arachnoid mater
    • Pia mater
  2. Group of Animals: All three meninges (dura mater, arachnoid mater, and pia mater) are found in vertebrate animals.