platyhelminthes

Question 1

phyla

Answer 1

catenulida
rhabitophora

Question 2

rhabitophora groups

Answer 2

turbellaria
castoda
monogenea
trematoda

Question 3

anatomic parts of a turbellarian

Answer 3

gastrovascular cavity, mesenchyme, muscle layers, ciliated epithelium

Question 4

parts of the ciliated epithelium

Answer 4

mucus glands
rhaboids/rhabdites
duogland adhesive system

Question 5

muscular layers

Answer 5

circular
diagonal
longitudinal

Question 6

modes of locomotion for turbellarians

Answer 6

undulatory swimming
ciliary gliding

Question 7

local examples of turbellarians

Answer 7

stylochus zebra
bdelloura candida

Question 8

turbellarian nutrition and feeding

Answer 8

incomplete gut
pharynx may be present, may be extended
scavengers and predators

Question 9

explain examples of gut and pharynx types

Question 10

nervous system of turbellarians

Answer 10

ladder like nervous system
- cephalization
- anterior cerebral ganglion
- longitudinal nerve cords
- transverse connectives

Question 11

sensory structures of turbellarians

Answer 11

chemoreceptors
ocelli
statocysts

Question 12

protonephridia

Answer 12

drain fluid from tissues and remove nitrogenous wastes along with them

Question 13

reproduction in turbellarians

Answer 13

generally occurs by copulation
hermaphroditic animals
reciprocal copulation is common
direct development of young

Question 14

turbellarian gonads

Answer 14

hermaphroditic
- male gonads: intermittent organ (= penis)
- female gonads - complicated egg structure with protective casing, nutritive yolk, very energy expensive

Question 15

reciprocal copulation

Answer 15

in turbellarians
both hermaphroditic animals fertilized at the same time
- hypodermic insemination can happen if there is no female gonophore for sperm to enter

Question 16

direct development

Answer 16

in turbellarians
no larval stage; hatching stage produces a juvenile that is similar to parents

Question 17

turbellarian eggs

Answer 17

laid in the environment

Question 17

turbellarian eggs

Answer 17

laid in the environment

Question 18

hypodermic insemination

Answer 18

in turbellarians where there is no female gonophore, male intermittent organ has a stylet that can pierce through the skin of another individual, and the sperm can travel to the ovoid
* in some species, the stylet is discarded and regenerated after each use, possibly to avoid STDs??

Question 19

penis fencing

Answer 19

occurs in only some species of turbellarians
both individuals fight to be the one to inseminate the other (thru hypodermic insemination??) in an attempt to pass on their genetic material and avoid energy expenditure of carrying offspring and reproducing

Question 20

lonely flatworms :(

Answer 20

in some species, it has been shown that if isolated, they will attempt to inseminate themselves
*unclear if this is successful

Question 21

Muller larva

Answer 21

in turbellarians
ciliated, oral flap, apical tuft, 8 ciliated tufts?
fun fact- used as the model for a pokemon

Question 22

Platyhelminthes major groups

Answer 22

Planaria, tapeworms and flukes

Question 23

Platyhelminthes orders (or just subgroups maybe?)

Answer 23

Catenulida
Rhabditophora
Turbellaria

Question 24

Catenulida

Answer 24

Subgroup of platyhelminthes - simple pharynx - sac like gut

Question 25

Rhabditophora

Answer 25

Subgroup of Platyhelminthes - poses rhabdites - duogland adhesive system

Question 26

Turbellaria

Answer 26

Subgroup of Rhabditophora Free living, commensal, and parasitic

Question 27

Subgroups of Rhabditophora

Answer 27

Turbellaria Cestoda Monogenea Trematoda

Question 28

Physical features of a Turbellarian

Answer 28

Body wall Mesenchyme Gastrovascular cavity

Question 29

Body wall of a Turbellarian

Answer 29

Contains ciliated epithelium and muscle layers

Question 30

Ciliated epithelium of a Turbellarian

Answer 30

Always Ciliated on the ventral side, sometimes but not always Ciliated on other areas - mucus gland cells sit between epithelial cells - rhaboids and rhabdites discharged from the epithelium in elongated packets- make up the duogland adhesive system

Question 31

Translocation in Turbellaria

Answer 31

Ciliary gliding- cilia beat in a coordinated manner, accompanied by mucus production in order to reduce friction - pure ciliary gliding only works for smaller animals, in larger it is aided by muscular action

Question 32

Muscle layers of turbellaria

Answer 32

Circular Diagonal Longitudinal

Question 33

Turbellarian locomotion

Answer 33

Undulatory swimming Ciliary gliding

Question 34

Undulatory swimming

Answer 34

Locomotion in Turbellaria

Question 35

Local Turbellarian examples

Answer 35

Stylochus zebra Bdelloura candida

Question 36

Rhaboids and rhabdites

Answer 36

Solid (mucus) structures that can be discharged by the epithelium Elongated packets Rhaboids- intracellular Rhabdites- intercellular - melt when discharged

Question 37

Duogland adhesive system

Answer 37

3 cell system 2 balloon/upside down vase like cells with a circular cell sandwiched between 1st cell: viscid cell, produces adhesive 2nd cell: anchor cell 3rd cell: produces solvent to break down the adhesive

Question 38

Function of rhaboids and rhabdites

Answer 38

May help facilitate locomotion, subdue prey Hard to prove these experimentally

Question 39

What are triploblasts?

Question 40

Germ layer

Answer 40

Later that forms in an early embryo that will correspond to certain tissues and structures in adults

Question 41

Layers of triploblasts

Answer 41

Ectoderm Endoderm Mesoderm

Question 42

Ectoderm

Answer 42

Outer covering of adult epithelium

Question 43

Endoderm

Answer 43

Gut and structures off of the gut

Question 44

Mesoderm

Answer 44

Muscle

Question 45

Which layers do cnidarians have?

Answer 45

Ectoderm and endoderm (All other animals are triploblasts, aka they have mesoderm) *cnidarians do still have muscles, but they just form in a different way

Question 46

Triclads

Answer 46

3 major branches of Gastrovascular cavity- 1 anterior and 2 posterior lateral (plus lots of minor branching) Extendable pharynx that attaches to the gvc Mouth opening at the end of the pharynx

Question 47

Polyclads

Answer 47

Gastrovascular cavities highly branched Scavengers- attracted to organic acids given off by decaying bodies

Question 48

Cephalization

Answer 48

Collection of nervous tissue near the anterior end

Question 49

Why does cephalization exist

Answer 49

Concentration of nerves and sensory tissues on the anterior end when the animal has a preferred direction of movement helps it quickly analyze its environment

Question 50

Turbellarian nervous system and sensory structures

Answer 50

Ladder like nervous system with: Cephalization Cerebral ganglion Longitudinal nerve cords Transverse connectives

Question 51

Turbellarian sensory structures

Answer 51

Ocelli Chemoreceptors (often on auricles) Statocysts

Question 52

Protonephridia

Answer 52

Network of flame cells etc in Turbellaria Draining fluid from the tissues and removing nitrogenous waste