Ch 13: Annelida

Question 1

6 annelid features

Answer 1

• most have a segmented body
• an obvious coelom
• protostome embryonic development
• chitinous chetae
• excretion via metanephridia
• marine spp have a trochophore larva

Question 2

2 coelom advantages

Answer 2

• hydrostatic skeleton

- provides space for viscera

Question 3

4 anatomical features of class Polychaeta

Answer 3

• head consists of prostomium and peristomium
• segments bear pairs of parapodia
• body wall has outer cuticle w/ protein fibers
• circular and longitudinal muscles

Question 4

parapodia features (2)

Answer 4

• surface used for gas exchange

- carry cheatae for grip and protection

Question 5

polychaete movement (2)

Answer 5

• burrowing spp pull themselves forwards w/ eversible proboscis
• some swim w/ undulating motion

Question 6

muscular eversible pharynx may have

Answer 6

jaws

Question 7

polychaetes circ system

Answer 7

closed

Question 8

3 features of polychaetes circ system

Answer 8

• no heart; contractile vessels and valves ensure one way flow
• segmental vessels lead to capillary beds around gut, body wall, parapods, metanephridia
• hemoglobin and other pigments, but not in cells

Question 9

2 funct of the 2 polychaete metanephridia

Answer 9

• collect coelomic fluid w/ cilia

- waste exits via nephridiopore

Question 10

what do polychaetes secrete

Answer 10

NH3

Question 11

what do polychaetes reabsorb (3)

Answer 11

water, salts, amino acids

Question 12

4 sensory organs in polychaetes

Answer 12

• tactile
• chemoreceptors
• statocysts
• eyes

Question 13

sexes in polychaetes

Answer 13

separate

Question 14

fert in polychaetes

Answer 14

open

Question 15

how are gametes of polychaetes prod?

Answer 15

by meiosis of cells lining coelom

Question 16

3 ways polychaete gametes can exit coelom

Answer 16

• nephridiopores
• special ducts
• rupture of body wall

Question 17

epitoke

Answer 17

nereids prod a special sexual stage - just for repro

Question 18

how are epitokes created

Answer 18

strobilization

Question 19

3 adaptations epitokes have for swimming

Answer 19

• bigger eyes
• enlarges muscles
• parapods

Question 20

errant polychaetes either ? or ?

Answer 20

crawl along the bottom, swim

Question 21

some errant polychaetes are in symbiotic relation to

Answer 21

a larger invert

Question 22

diets in errant polychaetes (3)

Answer 22

predators, scavengers, herbivores

Question 23

3 adaptations pelagic polychaetes have for swimming

Answer 23

• flattened bodies
• transparency
• big parapods

Question 24

3 things tube dwelling polychaetes tubes may be made from

Answer 24

• CaCO3
• protein
• cemented sand

Question 25

where are pogonophorans found? (3)

Answer 25

deep sea vents, methane seeps, whale falls

Question 26

what is unique about where pogonophorans are found?

Answer 26

all temp habitats

Question 27

what do pogonophoran tubes possess?

Answer 27

chitin

Question 28

what do pogonophorans have a symbiotic relationship w/?

Answer 28

chemosynthetic bacteria

Question 29

pogonophoran gut

Answer 29

none; simply collect gases for the bacteria

Question 30

3 features of class clitella

Answer 30

- clitella - external, glandular ring - hermaphrodites - permanent gonads

Question 31

clitellum

Answer 31

external glandular ring that secretes mucus which aids in sperm transfer, produces albumen, forms egg cocoon

Question 32

2 adaptations Oliogochaeta/earthworms have for burrowing

Answer 32

- no parapods | - fewer chetae

Question 33

2 things CaCO3 balls are for

Answer 33

- rid org of CO2 | - useful for mechanical digestion

Question 34

how many pairs of hearts do earthworms have

Answer 34

5

Question 35

how many blood vessels do earthworms have

Answer 35

2 - dorsal and ventral

Question 36

how are 1/5th of N-wastes expelled in earthworms

Answer 36

diffused across the cuticle

Question 37

how does gas exchange in earthworms occur

Answer 37

diffusion across cuticle

Question 38

3 ways an earthworm keeps its cuticle moist

Answer 38

- moist habitats - coelomic fluid leaks from pores - mucus keeps surface moist

Question 39

do earthworms have statosysts?

Answer 39

no

Question 40

3 repro ways in earthworms

Answer 40

- hermaphrodites (sexual) - parthenogenesis in patchy habitats some spp repro by fragmentation

Question 41

parthenogenesis

Answer 41

prod diploid eggs that don't need fert

Question 42

4 repro steps earthworms

Answer 42

- sperm transferred w/in mucus ring formed by clitellum - stored in spermathecae - eggs placed in 2nd mucus ring later which closes to form a 'cocoon' - direct development

Question 43

3 things earthworms do for soil

Answer 43

- mixing and aeration - bring nutrients towards surface - break down soil

Question 44

why are all earthworms in Canada exotic?

Answer 44

glaciation destroyed all local spp

Question 45

hirudinea

Answer 45

leeches

Question 46

what do leeches not have

Answer 46

chetae

Question 47

3 int features of leeches

Answer 47

- no internal septa - body usually flattened - coelom mostly filled w/ connective tissue and sinuses

Question 48

do leeches have a clitellum

Answer 48

yes; not obv

Question 49

leech locomotion (2)

Answer 49

- undulating swimmers | - inch along w/ suckers

Question 50

which sucker do leeches attach w/

Answer 50

posterior

Question 51

where are leeched mouths

Answer 51

in anterior sucker

Question 52

how do leeches create a wound before sucking ur blood (2)

Answer 52

- enzymes | - saw-toothed jaws

Question 53

pouches in digestive system hold blood up to ?x body weight

Answer 53

10

Question 54

class echiura features (3)

Answer 54

- unsegmented - ciliated proboscis for deposit feeding - marine bottom dwellers in U shaped burrow

Question 55

class sipuncula features (3)

Answer 55

- unsegmented burrowers - anterior introverts - deposit feeders who burrow in bottom or hide in crevices

Question 56

what does it mean to be an anterior introvert?

Answer 56

can take anterior end of body and invert/hide it inside rest of body