Porifora (+ Placozoa) Flashcards
what do sponges lack?
- mouth
- coelom
- muscles
- nervous, digestive, circulatory and excretory systems
- sex organs
- head
- gut
what traits confirm sponges as animals?
- collagen
- animal-like embryotic development
- septate junctions
- epithelial cells
- cells can unspecialize
- cell motility
what are ostia/dermal pores and the osculum?
ostia (one cell)/dermal pores (surrounded by several cells) = pore openings on sponges
osculum = outward-leading opening on sponges
what cells line the outside of a sponge?
pinacocytes (forms pinacoderm)
what cells line ostia?
porocytes
what are archaeocytes and what functions do they perform?
- cells found in mesohyl
- digests and stores food
- develops into gametes
- derived archaocytes can secrete spicules (sclerocytes) or spongin fibres (spongocytes)
what are the two layers of sponges and the matrix found between them?
- pinacoderm (outermost) and spongocoel (innermost)
- mesohyl in middle
what cells line the spongocoel and what are their functions?
- choanocytes/collar cells
- are flagellated
- generates current for water flow
- captures food and sperm
what are gemmules?
protected pods of unspecialized cells formed during inhospitable conditons
what are the three body forms possibly found in sponges?
leucenoid, ascenoid, sycnoid
briefly explain the body plan of leucenoid sponges
choanocytes form a complex network of chambers that lead to spongocoel
briefly explain the body plan of syconoid sponges
choanocytes form chambers that lead to spongocoel
briefly explain the body plan of ascenoid sponges
choanocytes line spongocoel
what sexual system are sponges?
hermaphroditic
how do sponges asexually reproduce?
- budding (parent forms a growth that detaches to regrow)
- fragmentation (piece of parent detaches and regrows)
- growth of gemmules
