Unit 8 Terms - Annelida

Question 1

Polychaete

Answer 1

• Means many long hair or long bristles
• Have well differentiated head and parapodia on most segments
• Mostly marine
• Examples: Clam Worms, Christmas Tree Worm and Sabellid

Question 2

Metameres

Answer 2

Repeating similar segments of a body, also known as somite or segment

Question 3

Annuli

Answer 3

Externally marked circular rings

Question 4

Metamerism

Answer 4

A division of the body into a series of segments

Question 5

Setae

Answer 5

Tiny chitinous bristles

Question 6

Prostomium

Answer 6

• Composes part of the head
• Anterior to the mouth
• First part of head

Question 7

Peristomium

Answer 7

• Composes part of the head

- Foremost true segment of an annelid, bears the mouth

Question 8

Pygidium

Answer 8

Posterior end of the worm, bears the anus

Question 9

Parapodia

Answer 9

• Flaps that may be present on each segment

- Variously modified for locomotion, respiration, or feeding

Question 10

What type of coelom formation?

Answer 10

Schizocoely

Question 11

Peritoneum

Answer 11

• A layer of mesodermal epithelium that lines the body wall of each compartment
• Forms dorsal and ventral mesenteries that cover all organs.

Question 12

Mesenteries

Answer 12

Peritoneal fold serving to hold the organ in position, double layer

Question 13

Hydrostatic skeleton

Answer 13

A mass of fluid or plastic parenchyma enclosed within a muscular wall to provide the support necessary for antagonistic muscle action

Question 14

Clitellum

Answer 14

• A reproductive structure found in Clitellata

- Example: Leeches or earthworms

Question 15

Characteristics of Phylum Annelida

Answer 15

• Means little ring
• 15,000 species
• Triploblastic

Question 16

Nephridia

Answer 16

• A pair for each segment

- Removes waste from blood as well as from coelom

Question 17

Nephrostome

Answer 17

• Means kidney mouth

- Opening of nephridia, cilliated funnel

Question 18

Nephridiopore

Answer 18

• Means kidney hole

- Exit for fluid waste from body

Question 19

Type of circulatory system

Answer 19

Closed

Question 20

Complete or incomplete gut?

Answer 20

Complete

Question 21

Notopodium

Answer 21

Big, thick lobe of the parapodia, closer to the dorsal side

Question 22

Neuropodium

Answer 22

Smaller lobe, closer to the ventral side

Question 23

Oligochaetes

Answer 23

• Means few bristles or long hairs
• Mostly freshwater
• Examples: earthworms

Question 24

Crop

Answer 24

Food storage, moves to the gizzard

Question 25

Gizzard

Answer 25

Grinds food before it enters the intestine

Question 26

Typhlosole

Answer 26

Infolding of intestinal wall to increase surface area and absorption

Question 27

Chlorogogen Tissue

Answer 27

Lines the outside of the intestine, helps form the typhlosole, produces fat and glycogen

Question 28

Eleocytes

Answer 28

• Fat cells, have been released from chlorogogen tissue

- May accumulate around wounds and regenerating areas

Question 29

Dorsal Vessel

Answer 29

Functions as the true heart in oligochaetes, pumps to propel blood

Question 30

Aortic Arches

Answer 30

Helps maintain blood pressure

Question 31

Ventral Vessel

Answer 31

Carries blood out to all the tissues of the body

Question 32

Hemoglobin

Answer 32

Pigment in blood, red

Question 33

Neurosecretory Cells

Answer 33

Make chemicals that regulate reproduction and regeneration

Question 34

Giant Axons

Answer 34

Nerve cells with high speed transmission, used for rapid escape