Tag: structural organization of rabbit

Questions Related to structural organization of rabbit

Presence of suckers are characteristic of which of the following class?

  1. Polychaeta

  2. Oligochaeta

  3. Hirudinea

  4. Archiannelida


Correct Option: C
Explanation:

Class Hirudinea belongs to phylum Annelida. These are parasitic in nature which is equipped with suckers used for creeping. Leeches are primarily freshwater annelids, but some live in the ocean and some in moist soil or vegetation. The majority of leeches are predators on small invertebrates, most swallow their prey whole, but some suck the soft parts from their victims. Some leeches are parasites rather than predators and suck the body fluids of their victims without killing them.

Therefore, the correct answer is option C.

A suctorial mouth is present in 

  1. Leech

  2. Ascaris

  3. Tapeworm

  4. Earthworm


Correct Option: A
Explanation:
  • Leeches are ectoparasites and they mostly live on the blood of vertebrate animals, like - humans, cattle, etc. They have a sanguivorous i.e. blood-sucking feeding habit. The blood-sucking habit of Leeches is supported by a special adaptation in their mouth.
  • Their mouth is a narrow triradiate aperture that sits at the center of the pre-oral chamber of the oral sucker. The oral sucker (or anterior sucker) is a tiny hollow muscular organ present at the anterior end of the animal body. 
  • The pre-oral chamber is actually a cup-like depression at the ventral surface of the oral sucker. One ray of the mouth is in medio-dorsal position, while the other two are placed ventro-laterally. 
  • This specially modified mouth of the Leeches is called suctorial mouth. When a feeding leech firmly adheres to the host body, its suctorial mouth moves like a saw and makes a triradiate (i.e. Y-shaped) painless incision in the victim's skin. Then the oozing blood of the host is sucked by the Leech. 

Match the locomotory organs given with the phylum, in which they are seen. Choose the answer which gives the correct combination of the alphabets of the two columns:

Locomotory organ Phylum
A. Pseudopodia p. Mollusca
B. Parapodia q. Chondrichthyes
C. Muscular foot r. Protozoa
D. Fins s. Annelida


  1. A- r, B- p, C- s, D- q

  2. A- p, B- r, C- s, D- q

  3. A- s, B- r, C- q, D- p

  4. A- r, B- s, C- p, D- q


Correct Option: D
Explanation:

Pseudopodia are the temporary extensions of the cytoplasm. These are used in locomotion and feeding. These are used by the protozoans and some of the flagellate protozoans. Polychaete worms  are the group of worms which belong to the phylum of Annelids. They are characterized by an elongated and segmented body. They bear a pair of appendages called parapodia on each metamere. These are used for locomotion. The organisms which are mollusc and belongs to the class of Gastropoda, have a flattened muscular foot for locomotion. They have a head that bears stalked eyes. Chondrichthyans are the group of cartilagenous fishes. Many chondrichthyans possess two dorsal fins, one anterior (just behind the head) and another posterior (in front of the tail).

Thus, the correct answer is option D. 

Which one of the following is a matching pair of a body feature and the animal possessing it?

  1. Ventral heart - Scorpion

  2. Post anal tail - Octopus

  3. Ventral central nervous system - Leech

  4. Pharyngeal gill slits absent in embryo- Chamaeleon


Correct Option: C
Explanation:

The scorpion heart is a strong, muscular organ extending along the dorsal mid-line of the heart.
Octopus has four pairs of arms, like all cephalopods.
Chamaeleon has pharyngeal gill slits in the embryo stage.
The central nervous system in leech is ventral.

Thus, the correct answer is option (C).

'Skate sucker' is the common name of 

  1. Hirudo

  2. Hirudinaria

  3. Pontobdella

  4. Nereis


Correct Option: C
Explanation:

Pontobdella is the type of leech. They are also known as skate sucker. It is the genus of leeches which includes bilaterally symmetrical animals. They belong to the class of Clitellata. It is marine leech. They are parasitic worms and attack skates and rays. They attach to the rock and wait to attack the skate. They also attack certain plaice. 

Thus, the correct answer is option C. 

External segmentation is absent but internal segmentation is present in

  1. Polychaeta

  2. Oligochaeta

  3. Archiannelida

  4. Hirudinea


Correct Option: C

Which of the following is an INCORRECT match?

  1. Polychaeta : Nereis

  2. Archiannelida : Polygordius

  3. Polychaeta : Hirudina

  4. Oligochaeta : Pheretima


Correct Option: C

Waste laden cells of oligochaetes and polychaetes are

  1. Thesocytes

  2. Eleocytes

  3. Follicular cells

  4. Yellow cells


Correct Option: D

Larva of Bonellia settling near proboscis of adult female develops into male due to.

  1. Substances secreted by proboscis

  2. Electrolytes in water

  3. Oxygen in environment

  4. Carbon dioxide in environment


Correct Option: A
Explanation:
Baltzer showed that if a Bonellia larva settles on the seafloor, it becomes a female. However, should a larva land on a female's proboscis (which apparently emits chemical signals that attract the larva), it enters the female's mouth, migrates into her uterus, and differentiates into a male. Thus, if a larva lands on the seafloor, it becomes female; if it settles on a proboscis, it becomes male.

So, the correct answer is 'Substances secreted by proboscis'.

Presence of Tubifex in water body indicates its

  1. Purity

  2. High salt content

  3. Toxic metals

  4. Organic loading


Correct Option: D
Explanation:

#Answer is option D.


#Tubifex worms mainly like nutrient-rich water, where bacterial growth is highest. Worms feed on bacteria and sludge.
#Bacterial growth takes place in water which has high organic loading. like, household organic waste, industrial organic waste, and agricultural waste.
#At this kind of places worms get food and places to hide from predators.