Sponges

Question 1

What are external features of sponges?

Answer 1

Brightly coloured (live sponges in aquarium)

 Body covered in pores- Porifera= pore bearer

 Can be tubular/flat/finger-like

 Sponges exhibit a variety of growth forms

Question 2

Describe the Ascenoid sponge

Answer 2

Large reservoir of
water
 Small SA:V ratio
 Inefficient use of
water
 Restricted to
smaller size
classes

Question 3

Describe the syconoid sponge

Answer 3

Larger SA:V ratio
 More efficient use
of water
 Still relatively
small size classes

Question 4

Describe the lueconoid sponge

Answer 4

Large SA:V ratio
 Most efficient use
of water
 Most sponges are
of this type
 Encrusting to
large, goblet
varieties

Question 5

Briefly describe the pinacocyte cell type

Answer 5

Pinacocytes- flattened cells that form the dermal
layer – Pinacoderm (line the outer layer of the
body)

Question 6

Briefly describe the porocyte cell types

Answer 6

tubular cells forming the intake pores

Question 7

Briefly describe the Choanocyte cell types

Answer 7

Collar cells lining the inner walls of the body- responsible for pulling water into the
sponge.

Question 8

Briefly describe the Archeocyte cell types

Answer 8

Archaeocytes- Amoeboid cells that move about
the mesohyl (area between the pinacocyte and
choanocyte). Totipotent- can become any of the
other cells, secrete skeletal structures and are
phagocytes.

Question 9

Differentiate between Medusa and polyp in cnidarians

Answer 9

Polyp
-Sessile
-Solitary or colonial
-Tubular
-Asexual reproduction

Medusa
-Motile/pelagic
-Solitary
-Resembles a bell/bag
-Sexual reproduction

Question 10

Cnidarians reproductive style?

Answer 10

They are dioecious (opposite of hermaphrodites)

Whereas sponges are hermaphrodites