BIO 172 UH MANOA | QUESTIONS AND ANSWERS | VERIFIED AND
WELL DETAILED ANSWERS | EXAM ALREADY GRADED A+ | LATEST
EXAM UPDATE
Endoderm
Mesoderm
Ectoderm - CORRECT ANSWER - Three embryonic layers. Endoderm being the
inner most layer and Ectoderm being the outermost.
What traits are present in the early stages of development that would not allow you
to determine if the animal is a protostome or deuterostome?
A) Radial Cleavage
B) presence of endoderm, mesoderm, and ectoderm
c) Coelom formed by splitting the mesodermal mass
D) Anus forms from blastopore
E) The developmental fate of each embryonic cell is fully determined -
CORRECT ANSWER - B) presence of endoderm, mesoderm, and ectoderm
Coelom - CORRECT ANSWER - Internal body cavity derived from the
mesoderm
Blastopore - CORRECT ANSWER - The opening that develops into the mouth in
protostomes and the anus in deuterostomes
,Radial Symmetry - CORRECT ANSWER - Can be split on multiple planes and
be symmetrical (Circle)
Ex. Adult Cnidaria
Bilateral symmetry - CORRECT ANSWER - Will only be symmetrical if split on
one line, all others will not be symmetrical (humans)
Ex. Nematoda
Rotational symmetry - CORRECT ANSWER - Division of the body into two
halves divides it into two copies of the same half with one rotated 180 degrees.
Ex. Ctenophora
Asymmetry - CORRECT ANSWER - No symmetry in any split
Ex. Porifera
Which is not a monophyletic group?
A) Opisthokonta
B) Bilateria
C) Cnidaria
D) Ctenophora
E) Porifera - CORRECT ANSWER - A) Opisthokonta
Which is true about animal evolutionary history?
,A) the Cambrian explosion led to the appearance of the Ediacaran biota
B) the Cambrian explosion occurred around 100 MYA
C) several extant phyla first appear in the fossil record from the Cambrian period
D) many fossils dating from the Cambrian explosion represent species that survive
today
E) the Cambrian explosion was caused by a rapid increase in Earth's atmospheric
nitrogen - CORRECT ANSWER - C) Several extant phyla first appear in the
fossil record from the Cambrian Period
Ediacaran Period - CORRECT ANSWER - before Cambrian period, about 635-
543 MYA
Cambrian Explosion/Period - CORRECT 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
E) food obtained via heterotrophy - CORRECT ANSWER - D) Alternation of
generations between diploid and haploid lifestages
, Hox Genes - CORRECT ANSWER - Responsible for the general body pattern of
most animals
Gastrulation - CORRECT ANSWER - results in the formation of the primitive
gut (archenteron) or digestive cavity and the formation of the embryonic layers.
Organogenesis - CORRECT 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
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. -
CORRECT 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
WELL DETAILED ANSWERS | EXAM ALREADY GRADED A+ | LATEST
EXAM UPDATE
Endoderm
Mesoderm
Ectoderm - CORRECT ANSWER - Three embryonic layers. Endoderm being the
inner most layer and Ectoderm being the outermost.
What traits are present in the early stages of development that would not allow you
to determine if the animal is a protostome or deuterostome?
A) Radial Cleavage
B) presence of endoderm, mesoderm, and ectoderm
c) Coelom formed by splitting the mesodermal mass
D) Anus forms from blastopore
E) The developmental fate of each embryonic cell is fully determined -
CORRECT ANSWER - B) presence of endoderm, mesoderm, and ectoderm
Coelom - CORRECT ANSWER - Internal body cavity derived from the
mesoderm
Blastopore - CORRECT ANSWER - The opening that develops into the mouth in
protostomes and the anus in deuterostomes
,Radial Symmetry - CORRECT ANSWER - Can be split on multiple planes and
be symmetrical (Circle)
Ex. Adult Cnidaria
Bilateral symmetry - CORRECT ANSWER - Will only be symmetrical if split on
one line, all others will not be symmetrical (humans)
Ex. Nematoda
Rotational symmetry - CORRECT ANSWER - Division of the body into two
halves divides it into two copies of the same half with one rotated 180 degrees.
Ex. Ctenophora
Asymmetry - CORRECT ANSWER - No symmetry in any split
Ex. Porifera
Which is not a monophyletic group?
A) Opisthokonta
B) Bilateria
C) Cnidaria
D) Ctenophora
E) Porifera - CORRECT ANSWER - A) Opisthokonta
Which is true about animal evolutionary history?
,A) the Cambrian explosion led to the appearance of the Ediacaran biota
B) the Cambrian explosion occurred around 100 MYA
C) several extant phyla first appear in the fossil record from the Cambrian period
D) many fossils dating from the Cambrian explosion represent species that survive
today
E) the Cambrian explosion was caused by a rapid increase in Earth's atmospheric
nitrogen - CORRECT ANSWER - C) Several extant phyla first appear in the
fossil record from the Cambrian Period
Ediacaran Period - CORRECT ANSWER - before Cambrian period, about 635-
543 MYA
Cambrian Explosion/Period - CORRECT 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
E) food obtained via heterotrophy - CORRECT ANSWER - D) Alternation of
generations between diploid and haploid lifestages
, Hox Genes - CORRECT ANSWER - Responsible for the general body pattern of
most animals
Gastrulation - CORRECT ANSWER - results in the formation of the primitive
gut (archenteron) or digestive cavity and the formation of the embryonic layers.
Organogenesis - CORRECT 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
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. -
CORRECT 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
