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which of the following has the most primitive respiratory system A.snail B.fish C.insect D.mouse?

which of the following has the most primitive respiratory system A.snail B.fish C.insect D.mouse?

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Answers (4)

isaaq
1 week ago
The answer is A.

Answer:
snail: but all these organisms are finely adapted to their respective habitat, including the snail.

Explanation:
Insects breathe air by the tracheal system. .

Fishes possess paired gills for breathing in water.

Mouse is a mammal and there are a pair of lungs for exchanging respiratory gases.

Compared to those three organisms, snails generally lack a particular respiratory organ. May be this could be regarded as evolutionarily primitive condition of its resiratory system.

Snails always remain in moist/muddy areas and breathe air through moist skin. Air enters mantle cavity through respiratory pore/pneumostome where surrounding skin remains highly vascularised. Blood carries respiratory gases, and participates in gas exchange.
EmX
1 week ago
The answer is A . (snails).

Before, attempting to move on. we need to lay down some facts.


As we climb upward to higher organisms, they possess less primitive organs, and systems. in order words the complexity increases.


As we know Vertebrates are higher than invertebrates based on classification.


And veterbrates include the following according to their increasing complexity.


Pices
  • EmX: The answer is A . (snails).

    Before, attempting to move on. we need to lay down some facts.


    As we climb upward to higher organisms, they possess less primitive organs, and systems. in order words the complexity increases.


    As we know Vertebrates are higher than invertebrates based on classification.


    And veterbrates include the following according to their increasing complexity.


    Pices......Amphibians.......Reptiles......Aves.....Mammals.


    There is increasing complexity in the chain from from left to right. mammals are the least primitive and most complex, while pices are the most primitive etc.. . but since Vertebrates are higher than invertebrates, most systems or the level of organisation ,in general, of pices is more complex/more developed than in the invertebrates.


    So back to the question.
    we cancel options D and B because they are both vertebrates, thus are higher than the remaining invertebrates.




    What we have left is A & C. (invertebrates).


    Now in invertebrates it also increase from 1 to 8 as shown below.
    (1)..Porifera (sponges) multicellularity, specialized cells but no tissues, asymmetry, incomplete digestive system sponges
    (2)..Cnidaria (jellyfish, corals) radial symmetry, true tissues, incomplete digestive system jellyfish
    (3)..Platyhelminthes (flatworms, tapeworms, flukes) cephalization, bilateral symmetry, mesoderm, complete digestive system flatworm
    (4)...Nematoda (roundworms) pseudocoelom, complete digestive system roundworm
    (5)..Mollusca (snails, clams, squids) true coelom, organ systems, some with primitive brain snail
    (6)..Annelida (earthworms, leeches, marine worms) segmented body, primitive brain earthworm
    (7)...Arthropoda (insects, spiders, crustaceans, centipedes) segmented body, jointed appendages, exoskeleton, brain insect (dragonfly)
    (8).Echinodermata (sea stars, sea urchins, sand dollars, sea cucumbers)

    According to this above,

    Molluscs (snails)...are less than Arthropdes (insects).

    Thus they are the most primitive.
    Snails have a thin skin permeable for water. On one hand that means that water snails also can breathe through their skin.
    But insects have a developed respiratory system involving the trachea and a opening to the external called the spiracles.

    Fishes receive oxygen into their respiratory system through their gills. and the mouse with is a mammal has the most developed respiratory system of them all.

    Which is the same as yours.
    Like 0    Dislike 0   1 week ago
Oluoma
1 week ago
Phyllum Mollisca has the most primitive respiratory system,and snail belongs to phylum Mollusca... So the answer is snail
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