Bilateral Symmetry Organisms

Question 0

Triploblastic

Answer 0

3 embryonic tissue layers

Question 1

Bilateral symmetry

Answer 1

Only one plane of bisection produces left and right mirror image halves
Polarized along 2 perpendicular axis

Question 2

Hydrostatic skeleton

Answer 2

Uses muscular contractions to displace fluid within a cavity exerting force and changing the shape of the cavity

Question 3

Phylum Platyhelminthes

Answer 3

Aka flatworms
Aquatic environments
Can be parasitic 
Cephalization
Incomplete digestive cavity 
Diffusion limited, lack circulatory system
Anterior ganglion and nerve cords
Monoecious (hermaphroditism)

Question 4

Parasitic worms

Answer 4

Flukes and tapeworms to humans
Turbellaria feed on small animals
Beating cilia

Question 5

Class Turbellaria

Answer 5

In phylum Platyhelminthes 
Free-living worm
Acoelomates
Marine environments mostly
A few hermaphroditic but mostly reproduce via copulation and cross fertilization 
E.g. Dugesia

Question 6

Dugesia

Answer 6

Flatworm
Food is sucked up and passes through pharynx, leads to a blind gastrovascular cavity with 3 lobes. Has light sensitive eyespots.

Question 7

Acoelomates

Answer 7

No body cavity apart from an alimentary canal. (Digestive tract)
E.g. Flatworm

Question 8

Pseudocoelomates

Answer 8

Have a body cavity between the endoderm and mesoderm. The body cavity is referred to as a pseudocoel.
E.g. Roundworm

Question 9

Coelomate

Answer 9

Cavity develops entirely within the mesoderm layer. This is called a true coelom. Sometimes coelomates are called eucoelomates.
E.g. Annelid

Question 10

Class Trematoda

Answer 10

Flukes
Parasites to human, some vertebrates
Endoparasites and ectoparasites 
Have an epicuticle adaption
No eyespots, or cilia 
Suckers
Reproduction cycle;
Intermediate host=snail, 2nd intermediate=fish, definitive host=vertebrate 
E.g. Fasciola

Question 11

Fasciola

Answer 11

Sheep liver flukes.
Swimming cilia larva called miracidium
Saclike sporocyst

Question 12

Opisthorchis sinensis

Answer 12

Oriental liver fluke
Lives in bile ducts of humans, cats, dogs, and pigs.
Consumption of raw fish
Can cause cirrhosis of the liver

Question 13

Schistosoma

Answer 13

Human blood flukes
Disease called schistosomiasis
Inhabits intestinal veins and other organs of hosts
Dioecious

Question 14

Class Cestoda

Answer 14

Aka tapeworms
Hang on inner walls of hosts intestinal tract
Absorb nutrients through epithelium
Lack digestive cavity
Has scolex (hooks and suckers), neck, and proglottids (segments).
Self fertilization on proglottids or cross fertilization.

Question 15

Phylum Nematoda

Answer 15

Aka roundworms 
Widespread and abundant
Homogeneous body plan (tapered at ends)
Pseudocoel between body wall and gut houses reproduction organs
Hydrostatic skeleton 
Move through eel like undulations

Question 16

Turbatrix, the vinegar eel

Answer 16

Free living nematode

Feeds on bacteria and yeast in dead organic material

Question 17

Ascaris, the intestinal roundworm

Answer 17

Infects humans

Spread through feces

Question 18

Trichinella

Answer 18

Nematode
Smallest to carnivorous animals
Causes trichinosis

Question 19

Hookworm and pinworm

Answer 19

Nematode
Hookworm causes anemia
Pinworms in children

Question 20

Filarial worms

Answer 20

Inhabit lymph glands usually in mammals and birds

Question 21

Wuchereria

Answer 21

Causes elephantiasis which is intense swelling of legs, breast, arms, scrotum

Question 22

Heart worm

Answer 22

Infects heart and pulmonary tissues in dogs

Question 23

Phylum Annelida

Answer 23

Aka earth worm, leeches and marine worms
Occur in various environments
Segmentation body creates specialization and improved hydrostatic skeleton.
Move through circular muscle contractions then longitudinal muscle contraction.
Have a closed circulatory system
Ventral nerve cord connects ganglia in each segment and to the brain

Question 24

Class Polychaeta

Answer 24

Phylum Annelida 
Marine environments
Symbiotic to chemo autotrophic bacteria
Segments have parapodia and setae (bristles)
Greatest amount of cephalization

Question 25

Class clitellata

Answer 25

Earth worms and leeches

Clitellum is a mucus secreting structure involved in reproduction

Question 26

Oligochaeta- earth worms

Answer 26

Also includes other fresh water worms such as blood worms or tubifex.
Lack parapodia and a well differentiated head region.
Decompose matter
Hermaphroditic
Clitellum is used in reproduction
Sperm produced in seminal vesicles and exits through male gonopores. Sperm travels through seminal grooves

Question 27

Hirudinea

Answer 27

Leeches 
Freshwater and marine
Blood suckers
E.g. Hirudo
Anticoagulants are secreted into host body
Segments lack internal septa
Have clitellum

Question 28

Phylum Platyhelminthes classes

Answer 28

Turbellaria
Trematoda
Cestoda
Includes species dugesia, fasciola, opisthorchis, schistosoma, tapeworm

Question 29

Phylum Nematoda species

Answer 29

Turbatrix, ascaris, trichinosis, hookworm, pinworm, filarial, heartworm

Question 30

Phylum Annelida classes

Answer 30

Polychaeta

Clitellata which includes Oligochaeta and hirudinea