Annelida

Question 1

What form did the ancestral Annelida larva come in?

Answer 1

Trochophore

Question 2

What size was the adult forms and 3 aspects of the bodies of ancestral Annelida?

Answer 2

Adults - small
Segments with pair of coelomic sac
chaetae (chitin bristles)/setae (stiff bristles)
no parapodia (muscular bristle appendages used for movement)

Question 3

Where were ancestral Annelida found?

Answer 3

Benthic (lowest levels of water) burrowing

Question 4

What symmetry is Annelida?

Answer 4

Bilateral

Question 5

What coelom and how does it form in Annelida?

Answer 5

Eucoelomate - formed by schizocoely = mesoderm separatesto form coelom

Question 6

Are Annelida segmented? Why?

Answer 6

Yes - arises form teloblastic growth (large cell divides into many smaller cells and specialize)

Question 7

What is the digestive tract and circulatory system of an Annelida?

Answer 7

Complete digestive

Closed circulatory

Question 8

Explain the nervous system of an Annelida (2)

Answer 8

Has dorsal cerebral ganglion (upper or backside, # of nerve cells) 
And ventral (underside) ganglionated nerve chord(s)

Question 9

Explain the head region of an Annelida (2)

Answer 9

Presegmental prostomium (1st body segment, anterior end, doesn’t include mount) and peristomium (2nd body segment, anterior end, contains mouth)

Question 10

How do Annelida reproduce?

Answer 10

Gonochoristic or hermaphroditic

Question 11

What are the 2 class of Annelida?

Answer 11

1- Polychaeta

2- Clitellata

Question 12

What 2 things does the class Polychaeta have?

Answer 12

1- parapodia (muscular bristled appendages ancestors don’t have) - for gass exchange and locomotion
2- acicula (support rods)

Question 13

What are the 2 subclasses of the class Polychaeta? Differences (found and parapodia)

Answer 13

1- Errantia - mobile/surface dwellers use parapodia as oars

2- Sedentaria - burrows parapodia reduced/modified/lost

Question 14

What are the 2 families of the class Polychaeta?

Answer 14

1- Nereidae

2- Arenicola

Question 15

What is an example of the family Nereidae of the class Polychaeta? Live? Important?

Answer 15

Nereis Virens
Live in tubes or burrows
Economically important bait worm

Question 16

What is an example of the family Arenicola of the class Polychaeta? Live?

Answer 16

Arenicola = lugworms

Live in burrows

Question 17

Explain the class Clitellata

Answer 17

Reduced # of segments with reproductive organs and clitellum (raised band around body with reproductive segments)

Question 18

What are the 2 subclasses of the class Clitellata?

Answer 18

1- Oligochaeta

2- Hirudinea

Question 19

How does the subclass Oligochaeta differ from the class Polychaeta?

Answer 19

Have setae but less than Polychaeta - used for locomotion and burrowing to prevent slipping

Question 20

What is the family under the subclass Oligochaeta of the class Clitellata?

Answer 20

Lumbricidae

Question 21

What is an example of the family Lumbricidae of the subclass Oligochaeta?

Answer 21

Lumbricus terrestris = earthworm

Question 22

How does Lumbricus terrestris (earthworms) of the family Lumbricidae move?

Answer 22

Peristalsis (Constriction and relaxation of the muscles = wave like motion) with setae used for anchorage

Question 23

What are the subclass Hirudinea?

Answer 23

Leeches

Question 24

What 2 things does the subclass Hirudinea of the class Oligochaeta lack?

Answer 24

No parapodia (appendages)
no setae (bristles)

Question 25

What is the family under the subclass Hirudinea of the class Oligochaeta?

Answer 25

Hirudinidae

Question 26

What is an example of the family Hirudinidae of the subclass Hirudinea? Used for?

Answer 26

Hirudo medicinalis = medical leech