Platyhelminthes

Question 1

What is the literal meaning of Platyhelminthes?

(greek)

Answer 1

Platys (flat)
Helminthes (worm)
Flatworms

Question 2

Body of the platyhelmintes

(think of the diagram)

Answer 2

Flatten dorsoventrally with a protuding mouth on its ventral side.

Question 3

Describe its morphology

Answer 3

• Elongated
• no legs
• Bilateral symmetic

Question 4

Platlyhelminthes are among the first animals to exhibit bilateral symmetry.

(true of false)

Answer 4

True

Question 5

Cephalisation

(platlyhelmintes have this)

Answer 5

differentiation of head.

Question 6

How many germ layers do platlyhelminthes have?

Answer 6

3 layers - Triploblastic

Question 7

Name the 3 germ layers found in Platlyhelminthes

Answer 7

Endoderm,ectoderm, mesoderm

Question 8

Discribe platlyminthes coelom

(what kind to they have?)

Answer 8

Acoelom. Do not have a fluid-filled body cavity

Question 9

the mesodermal cells or mesenchyme consit of?

Answer 9

Parenchyma

Question 10

What kind of organization do platlyhelminthes have?

Answer 10

Organ level grad organisation

Question 11

which worm does not have a gut?

(starts with cest : and is a tape)

Answer 11

Cestoidea tape worms

Question 12

What kind of guts do platyhelminthes have?

Answer 12

Incomeplete gut

Question 13

describe the modes of life of the platyhelminthes

Answer 13

free-living and parasitic.

Question 14

How many classes are there in platyhelminthes and name them.

Answer 14

1. tapeworms; Cestoidea
2. free-living flatworms;Turbellaria
3. flukes-parasitic flat worms; monogenea
4. flukes; Trematoda

Question 15

describe turbellaria

Answer 15

• freeliving below stones and marine debris
• symbiosis with orthers
• have cilia on epidermal calls

Question 16

What does the platyhelminthes digestive system include?

Answer 16

A pharynx
A mouth
An intestine

Question 17

What is the two type of feeding do Platyhelminthes utilizie

Answer 17

Scavengers and carnivores

(small insects, crustaceans, nematodes)

Question 18

How does turbellarian (planaria) detect food and food distance?

Answer 18

Chemoreceptors (food)
sensory cells on head (distance of food).

Question 19

What type of animal requires osmoregulation?

(what habitat do they live in?)

Answer 19

Freshwater animals

Question 20

Why does freshwater animals require osmoregulation?

Answer 20

Freshwater animals are hypertonic to their aquatic environments therefore need to osmoregulate.

Question 21

What allows for turbellarians to live in fresh water?

(starts with P and rhymes with photo)

Answer 21

Protonephridia

Question 22

What would happen to turbellarians if they had no protonephridia (flame cells)?

Answer 22

They would swell up.

Question 23

What is the name of the first kidney in platyhelminthes?

Answer 23

Protonephridia

Question 24

What does the flame cell have in it?

Answer 24

Cilia or flagella inside their cup-shaped body, that resombles a cell.

Question 25

What are the holes that flame cells excrete their waste from? | (from the word protonephridia)

Answer 25

Nephridiphores

Question 26

describe the osmoregulation and excretion in platyhelmintes.

Answer 26

The Platyhelminthes' metabolic waste is partly eliminated through their protonephridia and body walls. This occurs mainly through their body wall. The protonephridia is their first kidney and is also known as a flame cell. The flame cells have cilia or flagella, which beat and transport fluid to the collecting duct, creating a negative pressure, which draws the fluid from the surrounding tissue to the Tubule. The tubule then is merged and opens outside of the body wall, and waste is eliminated from the mesenchyme to the nephridiphores. Microvilli are responsible for water absorption to keep bodily fluids at the correct or ideal concentration.

Question 27

What does the nervous system consist of? | (6 THINGS. WHAT ARE THEY?)

Answer 27

1. Eyespot (Ocelli) 2. sensory lobe (Auricle) 3. Subepidermal Plexus 4. Brain (Cerebal Ganglia) 5. Longitudinal nerve chord. 6. Latteral branches

Question 28

Where are the sensory cells connected to? Anterior or posterior?

Answer 28

Anterior end of the flatworm that interacts with the environment first.

Question 29

Where are the nerve cells concentrated in the platyhelmintes

Answer 29

The cerebal ganglia (brain)

Question 30

Auricles what are their function and where are they located?

Answer 30

At the side of the head of the tubellarians. Have chemoreceptors concentrated in the auricles.

Question 31

Eyespots what are they

Answer 31

have dark pigments that look like a iris of a human and helps them detect light. | (pigment cups).

Question 32

Longitudinal nerve cords and latteral branches what do they do?

Answer 32

Responsible for most behavior.

Question 33

What is another word for latteral branches?

Answer 33

Commissures

Question 34

What gives the patyhelminthes its ladder structure

Answer 34

Combination of lateral branches (commissures) and the longitudinal nerve cords.

Question 35

What are the forms of locomotion in platyhelminthes?

Answer 35

Swimming (muscle contractions) and crawwing (ciliated ventral side of the organism and the flatten surface helps the worm move by crawing).