TAMU Biology 112 Lab
Practical 2 Exam Study Guide –
Practice Questions with
Verified Answers. GRADED A+.
Latest 2026/2027 Update.
Phylum Porifera - Answer✔✔-No true tissues
Asymmetrical symmetry
Taxa:
-Silicea (glass sponges)
-Calcarea (rest of sponges)
Osculum - Answer✔✔-Water exit in sponges
Spicules - Answer✔✔--Skeletal components of sponges made of silica, calcite
or spongin
-Produced by amoebocytes
Choanocytes - Answer✔✔-Spong's filter-feeding cells
,Phylum Cnidaria - Answer✔✔-Diploblastic
Radially symmetrical
Cnidocytes
Classes:
-Anthozoa
-Scyphozoa
-Cubozoa
-Hydrozoa
Two body plans of Phylum Cnidaria - Answer✔✔-Mobile medusa (sexual
reproduction)
Sessile polyp (asexual reproduction)
Cnidocytes - Answer✔✔-Specialized cells that contain stinging organelles called
nematocysts
Gastrovascular cavity in cnidarians - Answer✔✔-Serves as both a gut and a
hydrostatic skeleton
Single opening serves as both mouth and anus
Class Hydrozoa - Answer✔✔-Alternate between a dominant polyp stage and
less common medusa form
(Physalia pictured)
Obelia, Hydra, Physalia
, Class Scyphozoa - Answer✔✔-Dominant medusa form, reduced polyp
(Aurelia pictured)
Jellies
Class Anthozoa - Answer✔✔-Exist only as polyps
Sessile, often colonial
Sea anemones and corals
Reproduce asexually by fragmentation or sexually by production of gametes
Class Cubozoa - Answer✔✔-Box-shaped medusa
Box jellies, sea wasps
Unranked clade Ecdysozoa - Answer✔✔-Bilaterally symmetrical
Triploblastic
Protostome
Ecdysis: molt
Phyla:
-Nematoda
-Arthropoda
Protostome - Answer✔✔-Develop from splitting of embryonic mesoderm
Schizocoelous coelom
Determinate cell division
Spiral cleavage
Blastopore becomes mouth
Practical 2 Exam Study Guide –
Practice Questions with
Verified Answers. GRADED A+.
Latest 2026/2027 Update.
Phylum Porifera - Answer✔✔-No true tissues
Asymmetrical symmetry
Taxa:
-Silicea (glass sponges)
-Calcarea (rest of sponges)
Osculum - Answer✔✔-Water exit in sponges
Spicules - Answer✔✔--Skeletal components of sponges made of silica, calcite
or spongin
-Produced by amoebocytes
Choanocytes - Answer✔✔-Spong's filter-feeding cells
,Phylum Cnidaria - Answer✔✔-Diploblastic
Radially symmetrical
Cnidocytes
Classes:
-Anthozoa
-Scyphozoa
-Cubozoa
-Hydrozoa
Two body plans of Phylum Cnidaria - Answer✔✔-Mobile medusa (sexual
reproduction)
Sessile polyp (asexual reproduction)
Cnidocytes - Answer✔✔-Specialized cells that contain stinging organelles called
nematocysts
Gastrovascular cavity in cnidarians - Answer✔✔-Serves as both a gut and a
hydrostatic skeleton
Single opening serves as both mouth and anus
Class Hydrozoa - Answer✔✔-Alternate between a dominant polyp stage and
less common medusa form
(Physalia pictured)
Obelia, Hydra, Physalia
, Class Scyphozoa - Answer✔✔-Dominant medusa form, reduced polyp
(Aurelia pictured)
Jellies
Class Anthozoa - Answer✔✔-Exist only as polyps
Sessile, often colonial
Sea anemones and corals
Reproduce asexually by fragmentation or sexually by production of gametes
Class Cubozoa - Answer✔✔-Box-shaped medusa
Box jellies, sea wasps
Unranked clade Ecdysozoa - Answer✔✔-Bilaterally symmetrical
Triploblastic
Protostome
Ecdysis: molt
Phyla:
-Nematoda
-Arthropoda
Protostome - Answer✔✔-Develop from splitting of embryonic mesoderm
Schizocoelous coelom
Determinate cell division
Spiral cleavage
Blastopore becomes mouth
