BIOL371 MIDTERM EXAM ACTUAL QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS GRADED A++
What are the different symmetries?
Asymmetrical, Radial Symmetry, and Bilateral Symmetry.
What are the body cavities of Bilateria?
Acoelomate, Pseudocoelomate, Coelomate
Acoelomate
no cavity enclosing the gut
Pseudocoelomate
cavity enclosing the gut lined with mesoderm on outer side
Coelomate
gut suspended in cavity lined with mesoderm on both sides
Bilaterians are divided into:
Protostomes and Deuterostomes
Protostomes
mouth derived from blastopore, anus later; triploblastic
Deuterostomes
anus derived from blastopore, mouth later; triploblastic (Dookie comes from anus)
Metameric segmentation
repetition of segments and organ systems
Dorsal versus ventral orientation
, where the nervous and main elements of the circulatory system are situated
Phylum Ctenophora
comb jellies; diploblastic; biradial symmetry; gelatinous body
Phylum Porifera
neither diploblast or triploblasts; sponges; asymmetrical; sessile as adults
Phylum Cnidaria
jellyfish, sea anemones, corals; radial symmetry; diploblastic; medusa which is a
haploid
Cnidocytes and Nematocysts
How Cnidocytes sting; shared derived character
Lophotrochozoans
One of the two groups of protostomes. Lophotrochozoans include organisms that have
lophophores or trochophore larvae.
Ecdysozoans
One of the two groups of protostomes; shed their exoskeletons through a process called
ecdysis
Phylum Platyhelminthes
Lophotrochozoans; acoelomate; gut only has one opening
Phylum Mollusca
Lophotrochozoans; all have a soft body; body structure composed foot, mantle, and
visceral mass; bilateral
Phylum Annelida
Lophotrochozoans; well-defined segments with repetition
WITH COMPLETE SOLUTIONS GRADED A++
What are the different symmetries?
Asymmetrical, Radial Symmetry, and Bilateral Symmetry.
What are the body cavities of Bilateria?
Acoelomate, Pseudocoelomate, Coelomate
Acoelomate
no cavity enclosing the gut
Pseudocoelomate
cavity enclosing the gut lined with mesoderm on outer side
Coelomate
gut suspended in cavity lined with mesoderm on both sides
Bilaterians are divided into:
Protostomes and Deuterostomes
Protostomes
mouth derived from blastopore, anus later; triploblastic
Deuterostomes
anus derived from blastopore, mouth later; triploblastic (Dookie comes from anus)
Metameric segmentation
repetition of segments and organ systems
Dorsal versus ventral orientation
, where the nervous and main elements of the circulatory system are situated
Phylum Ctenophora
comb jellies; diploblastic; biradial symmetry; gelatinous body
Phylum Porifera
neither diploblast or triploblasts; sponges; asymmetrical; sessile as adults
Phylum Cnidaria
jellyfish, sea anemones, corals; radial symmetry; diploblastic; medusa which is a
haploid
Cnidocytes and Nematocysts
How Cnidocytes sting; shared derived character
Lophotrochozoans
One of the two groups of protostomes. Lophotrochozoans include organisms that have
lophophores or trochophore larvae.
Ecdysozoans
One of the two groups of protostomes; shed their exoskeletons through a process called
ecdysis
Phylum Platyhelminthes
Lophotrochozoans; acoelomate; gut only has one opening
Phylum Mollusca
Lophotrochozoans; all have a soft body; body structure composed foot, mantle, and
visceral mass; bilateral
Phylum Annelida
Lophotrochozoans; well-defined segments with repetition
