Nervous System
External Anatomy

Examine your earthworm and determine the dorsal and also ventral sides. Locate the clitellum which is on the anterior finish of the worm.

You are watching: Earthworm anatomy worksheet

Locate the mouth of the worm on the far anterior finish of the worm.The openings toward the anterior of the worm are the sperm ducts. The openings close to the clitellum are the genital setae. Label them on the worm pictured listed below.


Locate the dark line that runs down the dorsal side of the worm, this is the dorsal blood vessel. The ventral blood vessel can be viewed on the underside of the worm, though it is normally not as dark.

Label the earthworm pictured:

___________________________ ___________________________ ___________________________ ___________________________
Internal Anatomy Place the speciguys in the dissecting pan dorsal side up. Locate the clitellum and insert the tip of the scissors around 3 cm posterior (behind the clitellum). Cut very closely all the way up to the head. Try to save the scissors pointed up, and just cut via the skin. Spcheck out the skin of the worm out, usage a teasing needle to gently tear the septa (little thcheck out choose structures that organize the skin to organs below it) Place pins in the skin to host it apart, angle the pins out so that they are not in your method.
Reproductive System

The first structures you most likely check out are the seminal vesicles. They are cream colored and also located towards the anterior of the worm. These are used for producing sperm. Use tweezers to remove these white structures from over the peak of the digestive mechanism that lies underneath it.

See more: La To Toronto Flight S From Los Angeles To Toronto, Cheap Flights From Los Angeles To Toronto

Circulatory system

The dorsal blood vessel (X) appears as a dark brownish- red vessel running alengthy the intestine. The heart or aortic arches (Y) deserve to be discovered over the esophagus (just posterior to the pharynx). Carecompletely tease ameans the tproblems to expose the arches of the heart, the run throughout the worm. How many kind of aortic arches have the right to you count? ______The ventral blood vessel (Z) is oppowebsite the dorsal blood vessel, and cannot be watched at this time bereason the digestive mechanism covers it.Label the diagram (usage the letters alongside the bold words above)

worm circulatory device.pngearthworm anatomy worksheet