Phylum_Platyhelminthes_Report general characteristic.pptx

platyheminthes short report

1. Phylum Platyhelminthes (Flatworms) Prepared by: [Your Name] Subject: Biology / Zoology Teacher: [Teacher’s Name]

2. Introduction • Platyhelminthes are simple, soft-bodied, flattened worms. • Earliest animals to have bilateral symmetry. • Commonly known as flatworms. • Found in aquatic, moist terrestrial, or parasitic environments. Examples: Planaria, Tapeworm, Liver fluke.

3. General Characteristics 1. Dorsoventrally flattened body. 2. Triploblastic (three germ layers). 3. Acoelomate (no body cavity). 4. Bilateral symmetry. 5. Organ-system level of organization. 6. Incomplete digestive system (one opening). 7. No circulatory or respiratory systems. 8. Ladder-like nervous system.

4. Mode of Nutrition • Free-living flatworms (e.g., Planaria): - Carnivorous or scavengers. - Have a pharynx for sucking food. • Parasitic flatworms (e.g., Tapeworms, Flukes): - Absorb nutrients from host tissues or blood. - Adaptations: hooks, suckers, thick cuticle.

5. Mode of Reproduction • Asexual reproduction by regeneration (in Planaria). • Sexual reproduction: - Hermaphroditic (both male and female organs). - Fertilization can be cross or self. - Eggs develop into larvae or adults. • Parasitic species have complex life cycles with multiple hosts.

6. Summary • Bilateral symmetry, triploblastic, acoelomate. • Organ-system level of organization. • Nutrition: free-living (carnivorous) or parasitic (absorptive). • Reproduction: sexual and asexual with regeneration.

7. Examples • Planaria – Dugesia tigrina (freshwater, free-living) • Liver fluke – Fasciola hepatica (in liver of sheep/cattle) • Tapeworm – Taenia solium (in human intestine).

8. Fun Facts • Planarians can regrow their entire body from a small piece. • Some tapeworms can grow up to 30 feet long! • Among the first animals with a nervous system and bilateral symmetry.