Virtual Lab: Earthworm Dissection
Go to the following website:
Google Search Earthworm online dissection
http://www.mhhe.com/biosci/genbio/virtual_labs/BL_14/BL_14.html
Directions:
I. Read: Question:"What are the structures and body systems of an earthworm"(found on left side of screen)
a.) What is another name for segmented worm?
b.) What does segmentation support?
c.) What phylum are earthworms classified in?
d.) What other organism are classified as annedlida?
e.) What kind of symmetry do annelids have?
f.) What is a coelom?
g.) What is the basic body plan of a segmented worm?
h.) What is the term used for producing both sperm and eggs?
i.) Where is the capsule left after mating?
j.) How long does it take young earthworms to emerge from eggs?
k.) How do earthworms get food?
l.) How do earthworms help the soil and plants?
II. Read page 1-9 of the Lab Manual (hint: it is found on the bottom right hand corner of the screen)
Page 1 Questions- External Anatomy:
a.) What do scientists call the front end of the worm? The back end of the worm?
b.) What is the top side of the worm called? What is the bottom side of the worm called?
c.) How is a worm's body divided?
d.) What is a septum?
e.) What does an earthworm use setae for?
f.) At what segments are the mouth and anus located?
Page 2 questions- External Anatomy:
a.) What is the function of the clitellum?
b.) Where are the sperm duct openings found?
c.) Where do the sperm grooves run between?
d.) Where are the seminal receptacle openings?
e.) What do 2 earthworms exchange during mating? How are they aligned?
Page 3 questions-External Anatomy:
a.) Where do the oviducts have small openings next to? On what segment?
b.) What are dorsal pores?
c.) What are nephridia?
d.) What are the names of the openings where worms eliminated metabolic waste
through?
Page 4 questions- Internal Anatomy :
Look over the internal anatomy. You will have to label this diagram later.
a.) What systems are visible in this dissected worm?
Page 5 questions- The Digestive System
a.) What kind of digestive tract do earthworms have? Where does it run from?
b.) List the order of the structures of the digestive system from mouth cavity anus.
Mouth ___________ ______________ ______________ ______________ _____________ anus
c.) How does the pharynx aide is digestion?
d.) What is the function of the crop?
e.) What is the function of the gizzard?
f.) What happens to the nutrients as they pass through the intestine?
Page 6 questions- Nervous System
a.) Where is the simple brain located?
b.) What does the simple brain consist of?
c.) What has to be done in order to see the ventral nerve cord?
d.) What does the ventral nerve cord consist of?
Page 7 questions- Excretory System
a.) What are nephridia?
b.) Where are the nephridia found?
c.) What color are the nephridia?
d.) How do wastes exit the nephridia?
Page 8 questions- Reproductive System
a.) The earthworm is a hermaphrodite. What does that mean?
b.) What are seminal vesicles? Describe them. What matures in them?
c.) Where are the testes found?
d.) Where are the sperm ducts lead from the _____________________ to the __________________.
e.) Where can sperm ducts be found?
Page 9 Questions- Reproductive System
a.) What are seminal receptacles? What do they store?
b.) Where are seminal receptacles found?
c.) Describe the ovaries.
d.) Where are the ovaries attached?
e.) What is an egg sac? Where is it located?
f.) Where do the oviducts open on the surface?
III. Click on the External anatomy button to view a diagram of the external features
of an earthworm. Drag and drop the labels to the matching structures of the illustration. Click on the
Check button to receive feedback on whether the labels are matched with the correct structure. Correct
the highlighted incorrect labels, then on the diagram below.
IV. Click the Internal Anatomy button to view a diagram of the internal features of
the earthworm. Follow the same directions above.
Google Search: Earthworm Dissection Mount 1
Or
http://bioweb.uwlax.edu/zoolab/Table_of_Contents/Lab-6b/Earthworm_Mount_1/earthworm_mount_1.htm
LABEL 1-6
Click next
Label 1-3
Click Next
Label 1-12
Click next
Label 1-10