Q.5:- Distinguish between the following
(a) Prostomium and peristomium
(b) Septal nephridium and pharyngeal nephridium
Answer:-
(a)
|
Prostomium
|
Peristomium
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| Prostomium is a small fleshy lobe, which overhangs the mouth of an earthworm. It helps the organism push into the soil and is sensory in function. | The first body segment in the earthworm is called the peristomium. It surrounds the mouth opening. |
(b)
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Septal nephridium
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Pharyngeal nephridium
|
| They are present on both sides of inter-segmental septa behind the 15th segment. They open into the intestines. | They are present as three paired tufts in the fourth, fifth, and sixth segments. |