Question

phylum porifera study guide: questions: 14 mc

• know the classification criteria for phylum porifera
• the 3 cell types - function and recognize illustration

1.
2.
3.

• collar cells function
• the three ways sponges take in nutrients

1.
2.
3.

• how do sponges defend themselves?
• be able to tell the difference between the 3 types of sponges

Explanation:

Porifera are simple multicellular organisms. Classification criteria may involve skeletal structure. The three cell - types are pinacocytes (outer - layer protection), choanocytes (filter - feeding with flagella), and amoebocytes (nutrient transport and spicule formation). Collar cells (choanocytes) create water currents for filter - feeding. Sponges take in nutrients by filter - feeding, phagocytosis by amoebocytes, and absorption across cell membranes. They defend themselves with spicules (sharp structures), toxins, and symbiotic relationships. The three types of sponges (asconoid, syconoid, leuconoid) differ in canal and chamber complexity.

Answer:

Classification criteria: Skeletal structure and other morphological features.
Three cell - types: Pinacocytes (protection), choanocytes (filter - feeding), amoebocytes (nutrient transport and spicule formation).
Collar cells function: Create water currents for filter - feeding.
Three ways to take in nutrients: Filter - feeding, phagocytosis by amoebocytes, absorption across cell membranes.
Defense mechanisms: Spicules, toxins, symbiotic relationships.
Difference between 3 types of sponges: Canal and chamber complexity (asconoid simplest, leuconoid most complex).