Introduction to Helminthes and Mollusks

These flashcards cover key concepts from the study of helminthes and mollusks, focusing on their adaptations, anatomy, reproduction, and ecological importance.

What key adaptations do parasitic helminthes have?

They have gnarly adaptations to accommodate their unique way of life.

What is the function of flame cells in helminthes?

Flame cells function as rudimentary nephrons to help eliminate excess water and wastes.

How do freshwater organisms address excess water intake?

They eliminate excess water through an osmoregulatory system involving flame cells and tubules.

Why do marine organisms have a reduced osmoregulatory system?

Marine organisms battle dehydration and do not need to eliminate excess water.

What does cephalization refer to in flatworms?

Cephalization refers to the formation of a head in organisms.

What are the three types of neurons in flatworms?

Sensory neurons, motor neurons, and association (interneurons) neurons.

What is the purpose of the radula in mollusks?

The radula scrapes and pierces food particles before they are ingested.

How do bivalves feed?

Bivalves filter feed by pumping water over their gills and trapping food particles.

What is the basic body plan shared by all mollusks?

The basic body plan consists of a head-foot structure and a visceral mass.

What are the two forms of larval stages in many mollusks?

The two forms are the trochophore larvae and the veliger larvae.

How do mollusks generally reproduce?

Most mollusks are dioecious, having separate male and female individuals.

What problem do mollusks face due to ocean acidification?

Ocean acidification reduces calcium availability, making it difficult for mollusks to maintain strong shells.

What defines a definitive host in the life cycle of trematodes?

The definitive host is where the parasite is sexually mature and reproduces.

What is the role of ganglia in flatworm nervous systems?

Ganglia serve as clusters of neuronal cell bodies that help coordinate nerve signals.

What reproductive strategy helps flatworms maintain genetic diversity?

Cross-fertilization between hermaphroditic individuals helps maintain genetic diversity.

What are auricles in planarians and what is their function?

Auricles are ear-like lobes that contain sensory cells for touch and chemical detection.