Topic: Flatworms

1. Flatworms

Planarian
Tapeworm

2. Platyhelminthes (Flat Worms)

They have soft and flat bodies.
They show bilateral symmetry.
They have three tissue layers;
Ectoderm
Mesoderm
Endoderm

3. General characteristics of Flatworms

Ectoderm
Mesoderm
Endoderm
They have 3 tissue layers
They have bilateral symmetry

4.

They are hermaphroditic (can
produce both egg and sperm cells).
Have ladder-like nerves system.
Excretory organs are Flame cells
(protonephridia).
They have ladder-like nerves system

5.

Excretory organs
are Flame cells
(protonephridia)

6. Types of Flatworms

1. Turbellaria
Ex: Planarian
2. Trematoda
Ex: Flukes
3. Cestoda
Ex: Tapeworm

7. 1. Turbellaria: Characteristics of Planarian

Planaria is the most important example.
Mostly live in fresh water.
Have two eye spots.
Have only one opening at the centre serve as
mouth and anus.
The ability of regeneration is high.

8. Planarian

9. Regeneration of Planaria

The ability of an organism to regrow lost parts is called
regeneration.

10. Question

1. Which type of nerve system is found in the planarian?
A) Central
B) Radial
C) Ladder
D) Ganglial
E) Cord
2. Waste materials in the flatworms are excreted by
_____________.
A) Kidney
B) Nerves
C) Neuron
D) Protonephridia
E) Proglottis

11. Answers

1. Which type of nerve system is found in the planarian?
A) Central
B) Radial
C) Ladder
C)
Ladder
D) Ganglial
E) Cord
2. Waste materials in the flatworms are excreted by
_____________.
A) Kidney
B) Nerves
C) Neuron
D) Protonephridia
E) Proglottis
D)
Protonephridia

12. Question: Label the body parts of Planaria

13. Answer

14. 2) Trematoda

Example: Flukes
Flukes are the most important example.
They are parasite on vertebrates and human.
They use human and snail as a Host.
Ex: Blood flukes and Liver flukes.

15.

Life cycle of flukes

16.

Flukes in the liver

17. 3. Cestoda: Tapeworms

Tapeworms are the most important example.
They are parasite on vertebrates and human.
Have 2 body part Scolex (head) and
Proglottis (all body segments).
Have hooks and suckers on their scolex to
attach the host.

18. Body parts of Tapeworm

19. Scolex

Have no digestive system but have well developed
reproductive system (1 million egg in a day).
Ex: pork, beef, dog and fish tapeworm.
They have hooks and suckers on their Scolex to
attach the host.

20. Proglottis

Proglottis
They have no digestive system but have well
developed reproductive system
(1 million egg in a day)

21. Life cycle of Tapeworm

22. Questions

1. Which of the following lives in human liver as
parasite?
A) Flukes
B) Tapeworm
C) Earthworm
D) Ascarida
E) Trichina
2. Which structure produces egg and sperm cells in the
tapeworms?
A) Scolex
B) Sucker
C) Head
D) Hooks
E) Proglottids

23. Answers

1. Which of the following lives in human liver as
parasite?
A)
B) Tapeworm
A)Flukes
Flukes
C) Earthworm
D) Ascarida
E) Trichina
2. Which structure produces egg and sperm cells in the
tapeworms?
A) Scolex
B) Sucker
C) Head
D) Hooks
E)
E) Proglottids
Proglottids