Phylum Annelida

Question 1

General characteristics of phylum Annelida:

Answer 1

• bilateral symmetry
• eucoelom (true coelom)
• metameric segmentation
• has respiratory system eg. gills, skin, parapodia
• uses nephridia for excretory system
• has nervous system eg. ganglia, brain and sense organs
• has trocophore larva

Question 2

What are the characteristics of class Polychaeta?

Answer 2

• segments have parapodia
• includes errantia, which are predators or vegetarians or sedentaria that are filter or deposit feeders
• well developed sense organs
• NO permanent sex organs

Question 3

How do polychaetes reproduce?

Answer 3

• some produce buds
• most are dioecious (two sexes) and reproduce sexually
• external and internal fertilization
• has trocophore larva

Question 4

Characteristics of class Clitella:

Answer 4

• includes subclass Oligochaeta, which are the earth worms and aquatic worms
• LACK parapodia
• have clitellum, which is specialized region where embryos develop
• have setae (stiff, hair like structure)
• move through peristalsis
• hermaphroditic

Question 5

What are the characteristics of class Hirudinea?

Answer 5

• they are the leeches
• LACK paradodia and sensory structures on prostomium (head region)
• has clitellum
• LACK setae
• have suckers
• moves by looping
• hermaphroditic

Question 6

Characteristics of class Echiura:

Answer 6

• all marine
• unsegmented as adults but may have segments in embryonic nerve cord and coelomic pouches
• proboscis and ciliated funnel for feeding
• deposit or suspension feeders
• has trocophore larva

Question 7

What are the characteristics of class Sipunculid?

Answer 7

• known as peanut worms
• all marine
• deposit feeders
• unsegmented
• NO setae
• eucoelomate (true coelom)
• has trocophore larva