Worms.

Question 0

Triploblastic

Answer 0

3 tissue layers

Question 1

Platyhelmenthes

Answer 1

Flatworm “body flattened”

Question 2

What type of symmetry do playthelmenthes have?

Answer 2

Bilateral symmetry

Question 3

Level of development for platyhelmenthes

Answer 3

Organ system

Question 4

Acoelomate

Answer 4

Flatworms have no body cavity other than gut

Question 5

How does the lack of body cavities help respiration in Platyhelmenthes?

Answer 5

Allows them to be as flat as they can so that they can respire by diffusion. No cell is too far from the outside, flat shape necessary

Question 6

Parenchyma

Answer 6

Form of mesodermal tissue containing cells and tissue

Question 7

Planaria Characteristics

Answer 7

• negatively phototaxic
• chemoreception
• similar to u gut

Question 8

Rhabodites

Answer 8

Cells in planarians that form a protective mucus sheath around body

Question 9

Muscles in planarians

Answer 9

Run circularly, longitudely, and diagonally

Question 10

Digestion in Planarians

Answer 10

Mouth >> pharynx >> intestine
~ no anus
~ gut branched so it can deliver food to all parts of body
~ digestion completed intracellularly
~ waste out the pharynx

Question 11

Intestines in planarians

Answer 11

Secrete enzymes that break down food

Question 12

Flame cells

Answer 12

Collect water and waste and transport them into the cavity

Question 13

Cilia

Answer 13

Moves waste down extratory ducts

Question 14

Extrectory pores

Answer 14

Waste goes out

Question 15

Metabolic waste

Answer 15

Removed by diffusion through body wall

Question 16

Neurons in planarians

Answer 16

Sensory, motor, and association

Question 17

Sub epidermal nerve plexus

Answer 17

Very simple. Similar to a nerve net

Question 18

Reproduction in Planarians

Answer 18

Reproduce by fission (separate into two organisms, regenerate lost parts)
Monoecious but do not fertilize themselves, mate

Question 19

Class Turbellaria

Answer 19

Free living

Protrusible probasics

Question 20

Class Trematoda

Answer 20

Parasitic flukes, leaflike
Structural adaptation for prasitism
Poorly developed sense organs (Dont need them)

Question 21

2 hosts in Trematoda life cycle

Answer 21

Difinitive (snails) & intermediate (cows)

Question 22

Life cycle of trematoda

Answer 22

Cyst like eggs, need water
Larval trematodes enter snails & burrow
Burst through snail, kiling it
Swim upwards & incyst
Wait for host to eat it
Grows in next host (difinitive)

Question 23

Class Monogenes

Answer 23

External parasite

Enter gills & surface of fish
Simple lifestyle- single host
Economic impact

Question 24

Class cestoda

Answer 24

TAPEWORMSSS

Question 25

Digestive System jn tapeworms

Answer 25

Dont have one. Host already did digestion

Question 26

Microtriches in tapeworms

Answer 26

Cover entire surface to amplify surface area

Minute projections similar to microvilli

Question 27

Proglottid

Answer 27

Reproductive unit

Question 28

Strobila

Answer 28

Main body; chain of proglottids

Question 29

Reproduction in Tapeworms

Answer 29

Monoecious: one proglottis is fertalized by the same or different strobila
Mature proglottid detaches at prosterior end

Question 30

Tapeworms

Answer 30

4000 species, almost all require 2 hosts, parasites of vertebrate digestive tract