age 1 of 87
BIO 201 EXAM 3 2025/2026 COMPLETE QUESTIONS
WITH VERIFIED CORRECT SOLUTIONS || 100%
GUARANTEED PASS <LATEST VERSION>
Cambrian Explosion/Period .......Answer.........the most rapid
evolution of new animal phyla and animal diversity in Earth's
history about 542-488 MYA
Which of the following is not typical of most animals?
A) Specialized tissues
B) a stage of development called gastrulation
C) possession of hox genes
D) alternation of generations between diploid and haploid
lifestages
,age 2 of 87
E) food obtained via heterotrophy .......Answer.........D) Alternation
of generations between diploid and haploid lifestages
Hox Genes .......Answer.........Responsible for the general body
pattern of most animals
Gastrulation .......Answer.........results in the formation of the
primitive gut (archenteron) or digestive cavity and the formation
of the embryonic layers.
Organogenesis .......Answer.........formation of organs
Which of the following is true of the animal phylogenetic tree?
A) fossils provide the best source of information for determining
the animal phylogenetic tree
B) major accepted clades of the animal phylogeny have
remained constant over the past 50 years
,age 3 of 87
C) Future DNA evidence is likely to demonstrate that the
Bilateria is the most primitive animal clade
D) Eumetazoans include more species than Metazoans
E) As more DNA is sequenced and analyzed from more animals,
future changes to major surviving clades of the animal
phylogenetic tree become less likely. .......Answer.........E) As more
DNA is sequenced and analyzed from more animals, future
changes to major surviving clades of the animal phylogenetic
tree become less likely
Which of the following is not true of the coelom?
A) it may be present in triploblastic organisms
B) it is a cavity the houses internal organs
C) it is derived from mesoderm
, age 4 of 87
D) it is present in all animals
E) it usually contain fluids .......Answer.........D) it is present in all
animals
Triploblastic .......Answer.........Having 3 embryonic layers
(endoderm, mesoderm, and ectoderm)
Diploblastic .......Answer.........Having 2 embryonic layers
(endoderm and ectoderm).
Which of the following does not play a major role in Earth's
post-Cambrian animal evolution?
A) evolution among plants
B) meteor strikes
BIO 201 EXAM 3 2025/2026 COMPLETE QUESTIONS
WITH VERIFIED CORRECT SOLUTIONS || 100%
GUARANTEED PASS <LATEST VERSION>
Cambrian Explosion/Period .......Answer.........the most rapid
evolution of new animal phyla and animal diversity in Earth's
history about 542-488 MYA
Which of the following is not typical of most animals?
A) Specialized tissues
B) a stage of development called gastrulation
C) possession of hox genes
D) alternation of generations between diploid and haploid
lifestages
,age 2 of 87
E) food obtained via heterotrophy .......Answer.........D) Alternation
of generations between diploid and haploid lifestages
Hox Genes .......Answer.........Responsible for the general body
pattern of most animals
Gastrulation .......Answer.........results in the formation of the
primitive gut (archenteron) or digestive cavity and the formation
of the embryonic layers.
Organogenesis .......Answer.........formation of organs
Which of the following is true of the animal phylogenetic tree?
A) fossils provide the best source of information for determining
the animal phylogenetic tree
B) major accepted clades of the animal phylogeny have
remained constant over the past 50 years
,age 3 of 87
C) Future DNA evidence is likely to demonstrate that the
Bilateria is the most primitive animal clade
D) Eumetazoans include more species than Metazoans
E) As more DNA is sequenced and analyzed from more animals,
future changes to major surviving clades of the animal
phylogenetic tree become less likely. .......Answer.........E) As more
DNA is sequenced and analyzed from more animals, future
changes to major surviving clades of the animal phylogenetic
tree become less likely
Which of the following is not true of the coelom?
A) it may be present in triploblastic organisms
B) it is a cavity the houses internal organs
C) it is derived from mesoderm
, age 4 of 87
D) it is present in all animals
E) it usually contain fluids .......Answer.........D) it is present in all
animals
Triploblastic .......Answer.........Having 3 embryonic layers
(endoderm, mesoderm, and ectoderm)
Diploblastic .......Answer.........Having 2 embryonic layers
(endoderm and ectoderm).
Which of the following does not play a major role in Earth's
post-Cambrian animal evolution?
A) evolution among plants
B) meteor strikes
