Annelida

Question 1

What type of worms are phylum annelida

Answer 1

segmented worms

Question 2

why type of worms are included in phylum annelida

Answer 2

earthworms, polychaete worms and leeches

Question 3

what is another word for segmentation

Answer 3

metamerism

Question 4

what is first seen in annelids

Answer 4

coelom

between 2 mesodermal layers

Question 5

why are annelids more mobile than nematodes

Answer 5

hair like structures called SETAE (except leeches)

Sometimes located on paddle-like appendages called parapodia.

Question 6

Are annelids generally parasitic

Answer 6

no, they are just invertebrates

Question 7

what are the subgroups of phylum annelida

Answer 7

class oligochaeta (earthworms)
class polychaeta (marine worms)
class hirudinea (leeches)

Question 8

What are the important evolutionary changes in annelids

Answer 8

• coelom between 2 mesodermal layers
• big cerebral ganglia for touch and pressure
• blood vessels: open and closed closed means only carried in vessels
• pulsating vessels that move blood
• excretory system: metanephridia

Question 9

how can you compare metanephridia to nephrons of mammals

Answer 9

in our early embryonic life we have this primitive nephrostome as kidney then we develop Bowmans capsule as we grow

coelomic fluid filtered, useful solutes reabsorbed (like in mammals) urine excreted

Question 10

how do earthworms reproduce

Answer 10

hermaphrodites but avoids self fertilisation

• spermatozoa exchanged when fem+mal glued together
• when mating done, slime tube formed CITELLUM full of liquid
• earthworm moves forward out of the tube, tube pass fem pick egg, tube pass male pick sperm
• fertilzed eggs develop in closed citellum

Question 11

latin name for leeches and features

Answer 11

Hirudo medicinalis

• anterior and posterior sucker
• chitinous sharp teeth
• produces painkillers in saliva so bite does not hurt
• dont treatment disease as they dont vomit

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Question 12

How can leeches be used in medicine

Answer 12

after skin graft, they can stimulate circulation or clean blood clots