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Help me answer: Which one of the following correctly describes the location of some body parts in the earthworm Pheretima?

Which one of the following correctly describes the location of some body parts in the earthworm Pheretima?

• Option 1)

Four pairs of spermathecae in 4-7 segments

• Option 2)

One pair of ovaries attached at intersegmental septum of 14th and 15th segments

• Option 3)

Two pairs of testes in 10th and 11th segments

• Option 4)

Two pairs of accessory glands in 16-18 segments

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Earth worm (Pheretima Posthuma) -

it belongs to phylum Annelida, class-Oligochaeta. Earthworm is a nocturnal animal because it is sensitive to light.

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Spermathecae in earthworm -

Four pairs of spermathecae are present. one pair in each of 6th, 7th 8th and 9th segments. They receive and store the spematozoa of another earthworm during copulaiton.

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Body structure of Earthworm -

The body of earthworm has about 100-120 segments (metameric). The first segment is called as buccal segment or peristomium, which bears the opening of the mouth.

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Alimentary canal of earthworm -

it is straight tube and runs between the 1st and last segment of the body.

- wherein

1st - 3rd segment $\rightarrow$ Buccal cavity

4th segment $\rightarrow$ Pharynx

5th - 7th segment $\rightarrow$ Oesophagus

8th segment $\rightarrow$ Gizzard

9th - 14th segment $\rightarrow$ stomach with calciferous gland which produces $CaCO_{3}$   to neutralise the humic acid

15th - last segment $\rightarrow$ Intestine

Option 1)

Four pairs of spermathecae in 4-7 segments

This solution is incorrect

Option 2)

One pair of ovaries attached at intersegmental septum of 14th and 15th segments

This solution is incorrect

Option 3)

Two pairs of testes in 10th and 11th segments

This solution is correct

Option 4)

Two pairs of accessory glands in 16-18 segments

This solution is incorrect

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